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putnam_1966_a3
|
theorem putnam_1966_a3
(x : β β β)
(hx1 : 0 < x 1 β§ x 1 < 1)
(hxi : β n β₯ 1, x (n + 1) = (x n) * (1 - (x n)))
: Tendsto (fun n : β => n * (x n)) atTop (π 1) :=
sorry
|
124af5f076ccbe26
|
putnam_1976_a3
|
abbrev putnam_1976_a3_solution : Set (β Γ β Γ β Γ β) := sorry
-- {(3, 2, 2, 3), (2, 3, 3, 2)}
/--
Find all integer solutions $(p, r, q, s)$ of the equation $|p^r - q^s| = 1$, where $p$ and $q$ are prime and $r$ and $s$ are greater than $1$.
-/
theorem putnam_1976_a3
: {(p, r, q, s) : β Γ β Γ β Γ β | Nat.Prime p β§ Nat.Prime q β§ r > 1 β§ s > 1 β§ |(p^r : β€) - q^s| = 1} = putnam_1976_a3_solution :=
sorry
|
862d0def2897b578
|
putnam_2016_a2
|
abbrev putnam_2016_a2_solution : β := sorry
-- (3 + β 5) / 2
/--
Given a positive integer $n$, let $M(n)$ be the largest integer $m$ such that
\[
\binom{m}{n-1} > \binom{m-1}{n}.
\]
Evaluate
\[
\lim_{n \to \infty} \frac{M(n)}{n}.
\]
-/
theorem putnam_2016_a2
(M : β β β)
(hM : β n > 0, IsGreatest {m | 0 < m β§ (m - 1).choose n < m.choose (n - 1)} (M n)) :
Tendsto (fun n β¦ M n / (n : β)) atTop (π putnam_2016_a2_solution) :=
sorry
|
9a429a6325dfcc41
|
putnam_2024_b6
|
abbrev putnam_2024_b6_solution : β := sorry
-- -1/2
/--
For a real number $a$, let $F_a(x) = \sum_{n\geq 1} n^a e^{2n}x^{n^2}$ for $0 \leq x < 1$.
Find a real number $c$ such that $\lim_{x \to 1^-} F_a(x)e^{-1/(1-x)} = 0$ for all $a < c$, and $\lim_{x \to 1^-} F_a(x)e^{-1/(1-x)} = \infty$ for all $a > c$.
-/
theorem putnam_2024_b6
(F : β β β β β) (c : β)
(hF : β a, β x β Set.Ico 0 1,
HasSum (fun (n : β) => (n+1)^a * rexp (2*(n+1)) * x^(n+1)^2) (F a x)) :
((β a < c, Filter.Tendsto (fun x => F a x * rexp (- 1 / (1-x))) (π[<] 1) (π 0)) β§
(β a > c, Filter.Tendsto (fun x => F a x * rexp (- 1 / (1-x))) (π[<] 1) Filter.atTop))
β c = putnam_2024_b6_solution :=
sorry
|
750f7a8d6e992fe0
|
putnam_2019_b1
|
abbrev putnam_2019_b1_solution : β β β := sorry
-- (fun n : β => 5 * n + 1)
/--
Denote by $\mathbb{Z}^2$ the set of all points $(x,y)$ in the plane with integer coordinates. For each integer $n \geq 0$, let $P_n$ be the subset of $\mathbb{Z}^2$ consisting of the point $(0,0)$ together with all points $(x,y)$ such that $x^2+y^2=2^k$ for some integer $k \leq n$. Determine, as a function of $n$, the number of four-point subsets of $P_n$ whose elements are the vertices of a square.
-/
theorem putnam_2019_b1
(n : β)
(Pn : Set (Fin 2 β β€))
(pZtoR : (Fin 2 β β€) β EuclideanSpace β (Fin 2))
(sPnsquare : Finset (Fin 2 β β€) β Prop)
(hPn : Pn = {p | (p 0 = 0 β§ p 1 = 0) β¨ (β k β€ n, (p 0) ^ 2 + (p 1) ^ 2 = 2 ^ k)})
(hpZtoR : β p i, (pZtoR p) i = p i)
(sPnsquare_def : β sPn : Finset (Fin 2 β β€), sPnsquare sPn β (sPn.card = 4 β§ β p4 : Fin 4 β (Fin 2 β β€), Set.range p4 = sPn β§ (β s > 0, β i : Fin 4, dist (pZtoR (p4 i) : EuclideanSpace β (Fin 2)) (pZtoR (p4 (i + 1))) = s) β§ (dist (pZtoR (p4 0)) (pZtoR (p4 2)) = dist (pZtoR (p4 1)) (pZtoR (p4 3)))))
: {sPn : Finset (Fin 2 β β€) | (sPn : Set (Fin 2 β β€)) β Pn β§ sPnsquare sPn}.encard = putnam_2019_b1_solution n :=
sorry
|
5c2204ebc4ae6f1e
|
putnam_2009_b1
|
theorem putnam_2009_b1
(isquotprodprimefact : β β Prop)
(hisquotprodprimefact : β q, isquotprodprimefact q β
(β (k m : β) (a : Fin k β β) (b : Fin m β β),
(β i : Fin k, Nat.Prime (a i)) β§ (β j : Fin m, Nat.Prime (b j))
β§ (q = (β i : Fin k, Nat.factorial (a i))/(β j : Fin m, Nat.factorial (b j)))))
: β q : β, q > 0 β isquotprodprimefact q :=
sorry
|
006bfea59e7e6b9c
|
putnam_1993_a2
|
theorem putnam_1993_a2
(x : β β β)
(xnonzero : β n : β, x n β 0)
(hx : β n β₯ 1, (x n) ^ 2 - x (n - 1) * x (n + 1) = 1)
: β a : β, β n β₯ 1, x (n + 1) = a * x n - x (n - 1) :=
sorry
|
b053d947122d018b
|
putnam_1980_a4
|
theorem putnam_1980_a4
(abcvals : β€ β β€ β β€ β Prop)
(habcvals : β a b c : β€, abcvals a b c β (a = 0 β§ b = 0 β§ c = 0) β§ |a| < 1000000 β§ |b| < 1000000 β§ |c| < 1000000) :
(β a b c : β€,
abcvals a b c β§
|a + b * Real.sqrt 2 + c * Real.sqrt 3| < 10 ^ (-(11 : β))) β§
(β a b c : β€, abcvals a b c β |a + b * Real.sqrt 2 + c * Real.sqrt 3| > 10 ^ (-(21 : β))) :=
sorry
|
ff08cc69439ee179
|
putnam_1990_a4
|
abbrev putnam_1990_a4_solution : β := sorry
-- 3
/--
Consider a paper punch that can be centered at any point of the plane and that, when operated, removes from the plane precisely those points whose distance from the center is irrational. How many punches are needed to remove every point?
-/
theorem putnam_1990_a4
: sInf {n : β | β S : Set (EuclideanSpace β (Fin 2)), S.encard = n β§ β Q : EuclideanSpace β (Fin 2), β P β S, Irrational (dist P Q)} = putnam_1990_a4_solution :=
sorry
|
61fa14dd6910530f
|
putnam_2015_a4
|
abbrev putnam_2015_a4_solution : β := sorry
-- 4 / 7
/--
For each real number $x$, let
\[
f(x) = \sum_{n\in S_x} \frac{1}{2^n},
\]
where $S_x$ is the set of positive integers $n$ for which $\lfloor nx \rfloor$ is even. What is the largest real number $L$ such that $f(x) \geq L$ for all $x \in [0,1)$? (As usual, $\lfloor z \rfloor$ denotes the greatest integer less than or equal to $z$.)
-/
theorem putnam_2015_a4
(S : β β Set β€)
(f : β β β)
(p : β β Prop)
(hS : S = fun (x : β) β¦ {n : β€ | n > 0 β§ Even βn * xβ})
(hf : f = fun (x : β) β¦ β' n : S x, 1 / 2 ^ (n : β€))
(hp : β l, p l β β x β Set.Ico 0 1, f x β₯ l)
: IsGreatest p putnam_2015_a4_solution :=
sorry
|
5df6d46654f02eed
|
putnam_2005_a4
|
theorem putnam_2005_a4
(n : β)
(H : Matrix (Fin n) (Fin n) β)
(a b : β)
(S : Matrix (Fin a) (Fin b) β)
(npos : n β₯ 1)
(Hentries : β i j : Fin n, H i j = 1 β¨ H i j = -1)
(Hortho : H.HasOrthogonalRows)
(hab : 1 β€ a β§ a β€ n β§ 1 β€ b β§ b β€ n)
(Ssub : β (rri : Fin a β Fin n) (cri : Fin b β Fin n), rri.Injective β§ cri.Injective β§ S = H.submatrix rri cri)
(Sentries : β (i : Fin a) (j : Fin b), S i j = 1)
: a * b β€ n :=
sorry
|
51a6e7c5fee0f21c
|
putnam_1972_a1
|
theorem putnam_1972_a1
(n : β) (hn : n > 0)
(fourAP : β€ β β€ β β€ β β€ β Prop)
(hfourAP : β n1 n2 n3 n4, fourAP n1 n2 n3 n4 β n4-n3 = n3-n2 β§ n3-n2 = n2-n1) :
Β¬ β r : β, r > 0 β§ r + 3 β€ n β§ fourAP (n.choose r) (n.choose (r+1)) (n.choose (r+2)) (n.choose (r+3)) :=
sorry
|
783d78e37629142e
|
putnam_1962_a1
|
theorem putnam_1962_a1
(S : Set (β Γ β))
(hS : S.ncard = 5)
(hnoncol : β s β S, s.ncard = 3 β Β¬Collinear β s)
: β T β S, T.ncard = 4 β§ Β¬β t β T, t β convexHull β (T \ {t}) :=
sorry
|
d3ebc30ff4ca058d
|
putnam_1975_a5
|
theorem putnam_1975_a5
(I : Interval β)
(f y1 y2 : β β β)
(hfcont : Continuous f)
(hycdiff : ContDiff β 2 y1 β§ ContDiff β 2 y2)
(hy1sol : β x : β, iteratedDeriv 2 y1 x = (f x) * (y1 x))
(hy2sol : β x : β, iteratedDeriv 2 y2 x = (f x) * (y2 x))
(hylinindep : β c1 c2 : β, (β x : β, c1 * y1 x + c2 * y2 x = 0) β (c1 = 0 β§ c2 = 0))
(hyI : β x β I, y1 x > 0 β§ y2 x > 0)
: β c : β, c > 0 β§ (let z : β β β := fun x => c * Real.sqrt ((y1 x) * (y2 x)); β x β I, iteratedDeriv 2 z x + 1/(z x)^3 = (f x) * (z x)) :=
sorry
|
925a0432945ed286
|
putnam_1965_a5
|
abbrev putnam_1965_a5_solution : β β β := sorry
-- fun n => 2^(n - 1)
/--
How many orderings of the integers from $1$ to $n$ satisfy the condition that, for every integer $i$ except the first, there exists some earlier integer in the ordering which differs from $i$ by $1$?
-/
theorem putnam_1965_a5
: β n > 0, {p β permsOfFinset (Finset.Icc 1 n) | β m β Finset.Icc 2 n, β k β Finset.Ico 1 m, p m = p k + 1 β¨ p m = p k - 1}.card = putnam_1965_a5_solution n :=
sorry
|
bea1b81423927a9f
|
putnam_1988_b3
|
abbrev putnam_1988_b3_solution : β := sorry
-- (1 + Real.sqrt 3) / 2
/--
For every $n$ in the set $N=\{1,2,\dots\}$ of positive integers, let $r_n$ be the minimum value of $|c-d \sqrt{3}|$ for all nonnegative integers $c$ and $d$ with $c+d=n$. Find, with proof, the smallest positive real number $g$ with $r_n \leq g$ for all $n \in N$.
-/
theorem putnam_1988_b3
(r : β€ β β)
(hr : β n β₯ 1,
(β c d : β€,
(c β₯ 0 β§ d β₯ 0) β§
c + d = n β§ r n = |c - d * Real.sqrt 3|) β§
(β c d : β€, (c β₯ 0 β§ d β₯ 0 β§ c + d = n) β |c - d * Real.sqrt 3| β₯ r n))
: IsLeast {g : β | g > 0 β§ (β n : β€, n β₯ 1 β r n β€ g)} putnam_1988_b3_solution :=
sorry
|
3368febfcde43087
|
putnam_2020_b4
|
abbrev putnam_2020_b4_solution : β := sorry
-- 1 / 4040
/--
Let $n$ be a positive integer, and let $V_n$ be the set of integer $(2n+1)$-tuples $\mathbf{v} = (s_0, s_1, \cdots, s_{2n-1}, s_{2n})$ for which $s_0 = s_{2n} = 0$ and $|s_j - s_{j-1}| = 1$ for $j=1,2,\cdots,2n$. Define \[ q(\mathbf{v}) = 1 + \sum_{j=1}^{2n-1} 3^{s_j}, \] and let $M(n)$ be the average of $\frac{1}{q(\mathbf{v})}$ over all $\mathbf{v} \in V_n$. Evaluate $M(2020)$.
-/
theorem putnam_2020_b4
(V : β β Set (β β β€))
(q : β β (β β β€) β β)
(M : β β β)
(hV : V = fun n β¦ ({s : β β β€ | s 0 = 0 β§ (β j β₯ 2 * n, s j = 0) β§ (β j β Icc 1 (2 * n), |s j - s (j - 1)| = 1)}))
(hq : q = fun n s β¦ 1 + β j in Finset.Icc 1 (2 * n - 1), 3 ^ (s j))
(hM : M = fun n β¦ (β' v : V n, 1 / (q n v)) / (V n).ncard)
: (M 2020 = putnam_2020_b4_solution) :=
sorry
|
10f1f9763f543308
|
putnam_2004_a5
|
theorem putnam_2004_a5
(m n : β)
(mnpos : Inhabited (Fin m Γ Fin n))
(adj : (Fin m Γ Fin n) β (Fin m Γ Fin n) β Prop)
(connected : (Fin m Γ Fin n β Prop) β (Fin m Γ Fin n) β (Fin m Γ Fin n) β Prop)
(cmr : (Fin m Γ Fin n β Prop) β β)
(hadj : adj = fun (β¨a, _β©, β¨b, _β©) (β¨c, _β©, β¨d, _β©) β¦ a = c β§ Nat.dist b d = 1 β¨ b = d β§ Nat.dist a c = 1)
(hconnected : connected = fun C P Q β¦ β (S : List (Fin m Γ Fin n)) (hS : S β []),
S.head hS = P β§ S.getLast hS = Q β§ (β p : Prop, β i β Finset.range S.length, C S[i]! = p) β§ (β i β Finset.range (S.length - 1), adj S[i]! S[i+1]!))
(hcmr : cmr = fun C β¦ {R : Set (Fin m Γ Fin n) | β P β R, β Q, Q β R β connected C P Q}.ncard)
: (β C : Fin m Γ Fin n β Prop, cmr C > 2 ^ (m * n) * (m * n / (8 : β))) :=
sorry
|
0233cf9172791e68
|
putnam_2014_a5
|
theorem putnam_2014_a5
(P : β β Polynomial β)
(hP : β n, P n = β i in Finset.Icc 1 n, i * Polynomial.X ^ (i - 1))
: β (j k : β), (j > 0 β§ k > 0) β j β k β IsCoprime (P j) (P k) :=
sorry
|
7cf74d57af24c945
|
putnam_1991_a5
|
abbrev putnam_1991_a5_solution : β := sorry
-- 1 / 3
/--
Find the maximum value of $\int_0^y \sqrt{x^4+(y-y^2)^2}\,dx$ for $0 \leq y \leq 1$.
-/
theorem putnam_1991_a5
(f : Set.Icc (0 : β) 1 β β)
(hf : β y : Set.Icc 0 1, f y = β« x in Set.Ioo 0 y, Real.sqrt (x ^ 4 + (y - y ^ 2) ^ 2)) :
IsGreatest (f '' (Set.Icc 0 1)) putnam_1991_a5_solution :=
sorry
|
9c01ca3b1e4e1716
|
putnam_1981_a5
|
abbrev putnam_1981_a5_solution : Prop := sorry
-- True
/--
Let $P(x)$ be a polynomial with real coefficients; let $$Q(x) = (x^2 + 1)P(x)P'(x) + x((P(x))^2 + (P'(x))^2).$$
Given that $P$ has $n$ distinct real roots all greater than $1$, prove or disprove that $Q$ must have at least $2n - 1$ distinct real roots.
-/
theorem putnam_1981_a5
(Q : Polynomial β β Polynomial β)
(hQ : Q = fun P : Polynomial β => (X^2 + 1)*P*(derivative P) + X*(P^2 + (derivative P)^2))
(n : Polynomial β β β)
(hn : n = fun P : Polynomial β => ({x β Ioi 1 | P.eval x = 0}.ncard : β))
: (β P : Polynomial β, {x : β | (Q P).eval x = 0}.ncard β₯ 2*(n P) - 1) β putnam_1981_a5_solution :=
sorry
|
23e23d3a8c9f69f2
|
putnam_1986_a1
|
abbrev putnam_1986_a1_solution : β := sorry
-- 18
/--
Find, with explanation, the maximum value of $f(x)=x^3-3x$ on the set of all real numbers $x$ satisfying $x^4+36 \leq 13x^2$.
-/
theorem putnam_1986_a1
(S : Set β) (f : β β β)
(hS : S = {x : β | x ^ 4 + 36 β€ 13 * x ^ 2})
(hf : f = fun x β¦ x ^ 3 - 3 * x) :
IsGreatest
{f x | x β S}
putnam_1986_a1_solution :=
sorry
|
0f75686146092a9d
|
putnam_1989_b2
|
abbrev putnam_1989_b2_solution : Prop := sorry
-- True
/--
Let $S$ be a non-empty set with an associative operation that is left and right cancellative ($xy=xz$ implies $y=z$, and $yx=zx$ implies $y=z$). Assume that for every $a$ in $S$ the set $\{a^n:\,n=1, 2, 3, \ldots\}$ is finite. Must $S$ be a group?
-/
theorem putnam_1989_b2 :
(β (S : Type) [Nonempty S] [Semigroup S] [IsCancelMul S]
(h_fin : β a : S, {(a * Β·)^[n] a | n : β}.Finite),
β e : S, β x, e * x = x β§ x * e = x β§ β y, x * y = e β§ y * x = e) β
putnam_1989_b2_solution :=
sorry
|
d15a5b0e0cb2f6ff
|
putnam_2021_b5
|
theorem putnam_2021_b5
(n : β)
(npos : n β₯ 1)
(veryodd : Matrix (Fin n) (Fin n) β€ β Prop)
(hveryodd : β A, veryodd A β β m β Set.Icc 1 n, β reind : Fin m β Fin n, Function.Injective reind β Odd (A.submatrix reind reind).det)
: β A, veryodd A β (β k β₯ 1, veryodd (A ^ k)) :=
sorry
|
4904d260164ca0fb
|
putnam_1964_a4
|
theorem putnam_1964_a4
(u : β β β€)
(boundedu : β B T : β€, β n : β, B β€ u n β§ u n β€ T)
(hu : β n β₯ 4, u n = ((u (n - 1) + u (n - 2) + u (n - 3) * u (n - 4)) : β) / (u (n - 1) * u (n - 2) + u (n - 3) + u (n - 4)) β§ (u (n - 1) * u (n - 2) + u (n - 3) + u (n - 4)) β 0)
: (β N c : β, c > 0 β§ β n β₯ N, u (n + c) = u n) :=
sorry
|
e572ebab9b3d44de
|
putnam_1999_b2
|
theorem putnam_1999_b2
(P Q : Polynomial β)
(hQ : Q.natDegree = 2)
(hP : β x : β, P.eval x = (Q.eval x) * (Polynomial.derivative^[2] P).eval x) :
(β x1 x2, x1 β x2 β§ P.eval x1 = 0 β§ P.eval x2 = 0) β
(β f : Fin (P.natDegree) β β,
(β i j, i β j β f i β f j) β§
(β i, P.eval (f i) = 0)) :=
sorry
|
3f25619dab63bc71
|
putnam_1974_a4
|
abbrev putnam_1974_a4_solution : β β β := sorry
-- (fun n β¦ (1 : β) / (2 ^ (n - 1)) * (n * (n - 1).choose βn / 2ββ))
/--
Evaluate in closed form: $\frac{1}{2^{n-1}} \sum_{k < n/2} (n-2k)*{n \choose k}$.
-/
theorem putnam_1974_a4
(n : β)
(hn : 0 < n) :
(1 : β) / (2 ^ (n - 1)) * β k in Finset.Icc 0 βn / 2ββ, (n - 2 * k) * (n.choose k) =
putnam_1974_a4_solution n :=
sorry
|
83f368ab91d21a84
|
putnam_2003_a1
|
abbrev putnam_2003_a1_solution : β β β := sorry
-- fun n => n
/--
Let $n$ be a fixed positive integer. How many ways are there to write $n$ as a sum of positive integers, \[ n = a_1 + a_2 + \dots + a_k, \] with $k$ an arbitrary positive integer and $a_1 \leq a_2 \leq \dots \leq a_k \leq a_1 + 1$? For example, with $n = 4$, there are four ways: $4, 2 + 2, 1 + 1 + 2, 1 + 1 + 1 + 1$
-/
theorem putnam_2003_a1
(n : β) (hn : n > 0)
: Set.encard {a : β β β€ |
β k > 0, (β i : Fin k, a i = n) β§
(β i : Fin k, a i > 0) β§
(β i : Fin (k - 1), a i β€ a (i + 1)) β§
a (k - 1) β€ a 0 + 1 β§ (β i β₯ k, a i = 0)}
= putnam_2003_a1_solution n :=
sorry
|
ab4b405ebbe55c27
|
putnam_1977_a2
|
abbrev putnam_1977_a2_solution : β β β β β β β β Prop := sorry
-- fun a b c d β¦ d = a β§ b = -c β¨ d = b β§ a = -c β¨ d = c β§ a = -b
/--
Find all real solutions $(a, b, c, d)$ to the equations $a + b + c = d$, $\frac{1}{a} + \frac{1}{b} + \frac{1}{c} = \frac{1}{d}$.
-/
theorem putnam_1977_a2 :
β a b c d : β, putnam_1977_a2_solution a b c d β
a β 0 β b β 0 β c β 0 β d β 0 β (a + b + c = d β§ 1 / a + 1 / b + 1 / c = 1 / d) :=
sorry
|
33e0539de05c62df
|
putnam_1967_a2
|
theorem putnam_1967_a2
(S : β β β€)
(hS0 : S 0 = 1)
(hSn : β n β₯ 1, S n = {A : Matrix (Fin n) (Fin n) β | (β i j, A i j = A j i) β§ (β j, (β i, A i j) = 1)}.ncard) :
(β n β₯ 1, S (n + 1) = S n + n * S (n - 1)) β§
(β x : β, (β' n : β, S n * (x ^ n / (n)!)) = Real.exp (x + x ^ 2 / 2)) :=
sorry
|
e6b864edaccc45b1
|
putnam_2022_b3
|
abbrev putnam_2022_b3_solution : Prop := sorry
-- True
/--
Assign to each positive real number a color, either red or blue. Let $D$ be the set of all distances $d>0$ such that there are two points of the same color at distance $d$ apart. Recolor the positive reals so that the numbers in $D$ are red and the numbers not in $D$ are blue. If we iterate this recoloring process, will we always end up with all the numbers red after a finite number of steps?
-/
theorem putnam_2022_b3
(recolor : (β β Prop) β (β β Prop))
(hrecolor : β isred d, recolor isred d β β p q : β, p > 0 β§ q > 0 β§ p < q β§ isred p = isred q β§ q - p = d) :
(β isred, (β k, β p > 0, (recolor^[k] isred) p)) β putnam_2022_b3_solution :=
sorry
|
23831b3af829652a
|
putnam_1968_b1
|
theorem putnam_1968_b1
{Ξ© : Type*}
[MeasureSpace Ξ©]
[IsProbabilityMeasure (β : Measure Ξ©)]
(X Y : Ξ© β β€)
(hX : Measurable X)
(hY : Measurable Y)
(hX' : Set.Finite (X '' Set.univ))
(hY' : Set.Finite (Y '' Set.univ))
(k : β€) :
(β {Ο : Ξ© | min (X Ο) (Y Ο) = k}).toReal =
putnam_1968_b1_solution (β (Xβ»ΒΉ' {k})).toReal (β (Yβ»ΒΉ' {k})).toReal
(β {Ο : Ξ© | max (X Ο) (Y Ο) = k}).toReal :=
sorry
|
bb090240111a30b7
|
putnam_1982_a3
|
abbrev putnam_1982_a3_solution : β := sorry
-- (Real.pi / 2) * log Real.pi
/--
Evaluate $\int_0^{\infty} \frac{\tan^{-1}(\pi x) - \tan^{-1} x}{x} \, dx$.
-/
theorem putnam_1982_a3 :
Tendsto (fun t β¦ β« x in (0)..t, (arctan (Real.pi * x) - arctan x) / x) atTop (π putnam_1982_a3_solution) :=
sorry
|
5b093423bfb3ae0c
|
putnam_1992_a3
|
abbrev putnam_1992_a3_solution : β β Set (β Γ β Γ β) := sorry
-- fun m β¦ ite (Odd m) β
{(m + 1, 2 ^ (m / 2), 2 ^ (m / 2))}
/--
For a given positive integer $m$, find all triples $(n, x, y)$ of positive integers, with $n$ relatively prime to $m$, which satisfy
\[
(x^2 + y^2)^m = (xy)^n.
\]
-/
theorem putnam_1992_a3
(m : β)
(mpos : m > 0)
(S : Set (β Γ β Γ β))
(hS : β n x y : β, (n, x, y) β S β n > 0 β§ x > 0 β§ y > 0 β§ Coprime n m β§ (x ^ 2 + y ^ 2) ^ m = (x * y) ^ n)
: (S = putnam_1992_a3_solution m) :=
sorry
|
e1d5bd6cc7f4e84a
|
putnam_2017_a3
|
theorem putnam_2017_a3
(a b : β)
(f g : β β β)
(I : β β β)
(altb : a < b)
(fgcont : ContinuousOn f (Set.Icc a b) β§ ContinuousOn g (Set.Icc a b))
(fgimg : f '' (Set.Icc a b) β Set.Ioi 0 β§ g '' (Set.Icc a b) β Set.Ioi 0)
(fgint : β« x in Set.Ioo a b, f x = β« x in Set.Ioo a b, g x)
(fneg : β x : Set.Icc a b, f x β g x)
(hI : β n > 0, I n = β« x in Set.Ioo a b, ((f x) ^ (n + 1)) / ((g x) ^ n))
: (β n > 0, I (n + 1) > I n) β§ Tendsto I atTop atTop :=
sorry
|
3af9bcbaa227bb22
|
putnam_2007_a3
|
abbrev putnam_2007_a3_solution : β β β := sorry
-- fun k β¦ (k)! * (k + 1)! / ((3 * k + 1) * (2 * k)!)
/--
Let $k$ be a positive integer. Suppose that the integers $1, 2, 3, \dots, 3k+1$ are written down in random order. What is the probability that at no time during this process, the sum of the integers that have been written up to that time is a positive integer divisible by $3$? Your answer should be in closed form, but may include factorials.
-/
theorem putnam_2007_a3
(k : β)
(kpos : k > 0)
(perms : Set (Fin (3 * k + 1) β β€))
(goodperms : Set (Fin (3 * k + 1) β β€))
(hgoodperms : goodperms = {f β perms | Β¬β j : Fin (3 * k + 1), 3 β£ β i : Fin (3 * k + 1), ite (i β€ j) (f i) 0})
(hperms : perms = {f : Fin (3 * k + 1) β β€ | β y β Icc 1 (3 * k + 1), β! x : Fin (3 * k + 1), f x = y})
: (goodperms.ncard = perms.ncard * (putnam_2007_a3_solution k)) :=
sorry
|
401603179a5464db
|
putnam_1974_b2
|
theorem putnam_1974_b2
(y : β β β)
(ycontdiff : ContDiff β 1 y)
(limy : Tendsto (fun x : β => (deriv y x)^2 + (y x)^3) atTop (π 0))
: Tendsto y atTop (π 0) β§ Tendsto (deriv y) atTop (π 0) :=
sorry
|
84557fb2db81cc21
|
putnam_1999_a4
|
abbrev putnam_1999_a4_solution : β := sorry
-- 9/32
/--
Sum the series \[\sum_{m=1}^\infty \sum_{n=1}^\infty \frac{m^2 n}{3^m(n3^m+m3^n)}.\]
-/
theorem putnam_1999_a4
: Tendsto (fun i => β m in Finset.range i, β' n : β, (((m + 1)^2*(n+1))/(3^(m + 1) * ((n+1)*3^(m + 1) + (m + 1)*3^(n+1))) : β)) atTop (π putnam_1999_a4_solution) :=
sorry
|
cf3dc16f15c5604d
|
putnam_1964_b2
|
theorem putnam_1964_b2
(S : Type*) [Fintype S] [Nonempty S]
(P : Finset (Set S))
(hPP : β T β P, β U β P, T β© U β β
)
(hPS : Β¬β T : Set S, T β P β§ (β U β P, T β© U β β
))
: (P.card = 2 ^ (Fintype.card S - 1)) :=
sorry
|
93a69211f817ce71
|
putnam_2021_a3
|
abbrev putnam_2021_a3_solution : Set β := sorry
-- {3 * m ^ 2 | m > 0}
/--
Determine all positive integers $N$ for which the sphere $x^2+y^2+z^2=N$ has an inscribed regular tetrahedron whose vertices have integer coordinates.
-/
theorem putnam_2021_a3
(N : β)
(Nsphere : Set (EuclideanSpace β (Fin 3)))
(hNsphere : Nsphere = {p | (p 0) ^ 2 + (p 1) ^ 2 + (p 2) ^ 2 = (N : β)})
(intcoords : (EuclideanSpace β (Fin 3)) β Prop)
(intcoords_def : β p, intcoords p β β i : Fin 3, p i = round (p i)) :
(0 < N β§ β A B C D : EuclideanSpace β (Fin 3),
A β Nsphere β§ B β Nsphere β§ C β Nsphere β§ D β Nsphere β§
intcoords A β§ intcoords B β§ intcoords C β§ intcoords D β§
(β s > 0, dist A B = s β§ dist A C = s β§ dist A D = s β§ dist B C = s β§ dist B D = s β§ dist C D = s))
β N β putnam_2021_a3_solution :=
sorry
|
8dc16a1abd9a5115
|
putnam_1981_b3
|
theorem putnam_1981_b3
(P : β β Prop)
(hP : β n, P n β
β p : β, (Nat.Prime p β§ p β£ n^2 + 3) β
β k : β, (p : β€) β£ (k : β€)^2 + 3 β§ k^2 < n) :
β n : β, β m : β, (m : β€) > n β§ P m :=
sorry
|
69455b04ba7935f9
|
putnam_2014_b3
|
theorem putnam_2014_b3
(m n : β)
(A : Matrix (Fin m) (Fin n) β)
(mnpos : 0 < m β§ 0 < n)
(Aprime : {p : β | p.Prime β§ β (i : Fin m) (j : Fin n), |A i j| = p}.encard β₯ m + n)
: A.rank β₯ 2 :=
sorry
|
09ad2f6350fe0c39
|
putnam_1963_b6
|
theorem putnam_1963_b6
(d : β)
(S : Set (Fin d β β) β Set (Fin d β β))
(hS : S = fun A : Set (Fin d β β) => β p β A, β q β A, segment β p q)
(A : β β Set (Fin d β β))
(ddim : 1 β€ d β§ d β€ 3)
(hA0 : Nonempty (A 0))
(hAn : β n β₯ 1, A n = S (A (n - 1)))
: β n β₯ 2, A n = A (n + 1) :=
sorry
|
0efae5679cacf7cf
|
putnam_2007_b5
|
theorem putnam_2007_b5
(k : β) (kpos : k > 0) :
(β P : Finset.range k β Polynomial β, β n : β€, β(n : β) / kβ ^ k = β i : Finset.range k, (P i).eval (n : β) * β(n : β) / kβ ^ (i : β)) :=
sorry
|
f8c04b94868a178e
|
putnam_2018_a6
|
theorem putnam_2018_a6
(A B C D : EuclideanSpace β (Fin 2))
(PPprops : (EuclideanSpace β (Fin 2)) β (EuclideanSpace β (Fin 2)) β Prop)
(hPPprops : β P1 P2, PPprops P1 P2 β P1 β P2 β§ (β q : β, (dist P1 P2) ^ 2 = q))
(ABCDnoline : Β¬Collinear β {A, B, C} β§ Β¬Collinear β {A, B, D} β§ Β¬Collinear β {A, C, D} β§ Β¬Collinear β {B, C, D})
(ABCDsqrrat : PPprops A B β§ PPprops A C β§ PPprops A D β§ PPprops B C β§ PPprops B D β§ PPprops C D) :
β q : β, (MeasureTheory.volume (convexHull β {A, B, C}) / MeasureTheory.volume (convexHull β {A, B, D})).toReal = q :=
sorry
|
d37e57c80fc12cb7
|
putnam_2008_a6
|
theorem putnam_2008_a6
: β c : β, c > 0 β§ β G [Group G] (fing : Fintype G), fing.card > 1 β β s : List G, s.length β€ c * Real.log (fing.card : β) β§ β g : G, β t : List G, t.Sublist s β§ t.prod = g :=
sorry
|
3dd246f25e079383
|
putnam_1992_b5
|
abbrev putnam_1992_b5_solution : Prop := sorry
-- False
/--
Let $D_n$ denote the value of the $(n-1) \times (n-1)$ determinant
\[
\left[
\begin{array}{cccccc}
3 & 1 & 1 & 1 & \cdots & 1 \\
1 & 4 & 1 & 1 & \cdots & 1 \\
1 & 1 & 5 & 1 & \cdots & 1 \\
1 & 1 & 1 & 6 & \cdots & 1 \\
\vdots & \vdots & \vdots & \vdots & \ddots & \vdots \\
1 & 1 & 1 & 1 & \cdots & n+1
\end{array}
\right].
\]
Is the set $\left\{ \frac{D_n}{n!} \right\}_{n \geq 2}$ bounded?
-/
theorem putnam_1992_b5
(D : β β β)
(hD : β n, D n = Matrix.det (fun i j : Fin (n - 1) β¦ ite (i = j) ((i : β) + 3 : β) 1)) :
putnam_1992_b5_solution β (Bornology.IsBounded {x | β n β₯ 2, D n / factorial n = x}) :=
sorry
|
f3eb7c554c502eb1
|
putnam_1982_b5
|
theorem putnam_1982_b5
(T : Set β)
(hT : T = Ioi (Real.exp (Real.exp 1)))
(S : β β β β β)
(hS : β x β T, S x 0 = (Real.exp 1) β§ β n : β, S x (n + 1) = Real.logb (S x n) x)
(g : β β β)
: β x β T, (β L : β, Tendsto (S x) atTop (π L)) β§
(β x β T, Tendsto (S x) atTop (π (g x))) β ContinuousOn g T :=
sorry
|
f54a48576fb94620
|
putnam_1995_b1
|
theorem putnam_1995_b1
(Pi : Finpartition (Finset.range 9) β (Finset.range 9) β β)
(Pi_def : β partition k, Pi partition k = (Exists.choose (Finpartition.exists_mem partition k.2)).card) :
β Pt1 Pt2,
β x y : Finset.range 9,
x β y β§
Pi Pt1 x = Pi Pt1 y β§
Pi Pt2 x = Pi Pt2 y :=
sorry
|
97bc2d5e556b2325
|
putnam_1985_b1
|
abbrev putnam_1985_b1_solution : Fin 5 β β€ := sorry
-- fun i β¦ i - 2
/--
Let $k$ be the smallest positive integer for which there exist distinct integers $m_1, m_2, m_3, m_4, m_5$ such that the polynomial
\[
p(x) = (x-m_1)(x-m_2)(x-m_3)(x-m_4)(x-m_5)
\]
has exactly $k$ nonzero coefficients. Find, with proof, a set of integers $m_1, m_2, m_3, m_4, m_5$ for which this minimum $k$ is achieved.
-/
theorem putnam_1985_b1
(p : (Fin 5 β β€) β (Polynomial β))
(hp : p = fun m β¦ β i : Fin 5, ((X : Polynomial β) - m i))
(numnzcoeff : Polynomial β β β)
(hnumnzcoeff : numnzcoeff = fun p β¦ {j β Finset.range (p.natDegree + 1) | coeff p j β 0}.card)
: (Injective putnam_1985_b1_solution β§ β m : Fin 5 β β€, Injective m β numnzcoeff (p putnam_1985_b1_solution) β€ numnzcoeff (p m)) :=
sorry
|
1cd2a135e3317ce2
|
putnam_2000_b1
|
theorem putnam_2000_b1
(N : β)
(a b c : Fin N β β€)
(Nge1 : N β₯ 1)
(hodd : β j : Fin N, Odd (a j) β¨ Odd (b j) β¨ Odd (c j))
: (β r s t : β€, {j : Fin N | Odd (r * a j + s * b j + t * c j)}.ncard β₯ (4 * N : β) / 7) :=
sorry
|
d682645997fe5e07
|
putnam_2010_b1
|
abbrev putnam_2010_b1_solution : Prop := sorry
-- False
/--
Is there an infinite sequence of real numbers $a_1, a_2, a_3, \dots$ such that \[ a_1^m + a_2^m + a_3^m + \cdots = m \] for every positive integer $m$?
-/
theorem putnam_2010_b1
: (β a : β β β, β m : β, m > 0 β β' i : β, (a i)^m = m) β putnam_2010_b1_solution :=
sorry
|
6f698b814fd07be3
|
putnam_2022_a5
|
abbrev putnam_2022_a5_solution : β := sorry
-- 290
/--
Alice and Bob play a game on a board consisting of one row of 2022 consecutive squares. They take turns placing tiles that cover two adjacent squares, with Alice going first. By rule, a tile must not cover a square that is already covered by another tile. The game ends when no tile can be placed according to this rule. Alice's goal is to maximize the number of uncovered squares when the game ends; Bob's goal is to minimize it. What is the greatest number of uncovered squares that Alice can ensure at the end of the game, no matter how Bob plays?
-/
theorem putnam_2022_a5
(IsValidMove : Set (Fin 2022) β Set (Fin 2022) β Prop)
(IsValidMove_def : β x y, IsValidMove x y β
(x = y β§ β i < 2021, i β x β i + 1 β x) β¨
β i < 2021, i β x β§ i + 1 β x β§ y = x βͺ {i, i + 1})
(IsValidGame : List (Set (Fin 2022)) β Prop)
(IsValidGame_def : β g, IsValidGame g β (β gt, g = β
:: gt) β§ g.Chain' IsValidMove)
(ConformsToStrategy : List (Set (Fin 2022)) β (Set (Fin 2022) β Set (Fin 2022)) β Prop)
(ConformsToStrategy_def : β g s, ConformsToStrategy g s β
β (i) (h : i + 1 < g.length), Even i β g[i + 1] = s g[i]) :
IsGreatest
{n | β s, (β x, IsValidMove x (s x)) β§ β g,
IsValidGame g β ConformsToStrategy g s β β gh x, g = gh ++ [x] β§ n β€ xαΆ.ncard}
putnam_2022_a5_solution :=
sorry
|
801c2afeea8551e0
|
putnam_1967_b4
|
theorem putnam_1967_b4
(n : β)
(lockers : β β Set.Icc 1 n β Bool)
(npos : n β₯ 1)
(hlockers0 : β i : Set.Icc 1 n, lockers 0 i = false)
(hlockersk : β k β Set.Icc 1 n, β i : Set.Icc 1 n, lockers k i = if k β£ i then !(lockers (k - 1) i) else (lockers (k - 1) i))
: β i : Set.Icc 1 n, lockers n i β (β j : β€, j ^ 2 = i) :=
sorry
|
387764c8bc3ec09d
|
putnam_1983_b4
|
theorem putnam_1983_b4
(f : β β β€)
(a : β β β)
(hf : f = fun (n : β) β¦ n + Int.floor (βn))
(ha0 : a 0 > 0)
(han : β n : β, a (n + 1) = f (a n)) :
(β i : β, β s : β€, a i = s ^ 2) :=
sorry
|
7425198cbd334f35
|
putnam_1993_b4
|
theorem putnam_1993_b4
(K : β Γ β β β)
(f g : β β β)
(Kpos : β x y : Set.Icc (0 : β) 1, K (x, y) > 0)
(Kcont : ContinuousOn K {(x, y) : β Γ β | x β Set.Icc 0 1 β§ y β Set.Icc 0 1})
(fgpos : β x : Set.Icc (0 : β) 1, f x > 0 β§ g x > 0)
(fgcont : ContinuousOn f (Set.Icc 0 1) β§ ContinuousOn g (Set.Icc 0 1))
(fgint : β x : Set.Icc (0 : β) 1, (β« y in Set.Ioo 0 1, f y * K (x, y)) = g x β§ (β« y in Set.Ioo 0 1, g y * K (x, y)) = f x)
: β x : Set.Icc (0 : β) 1, f x = g x :=
sorry
|
99f34e09d17013ef
|
putnam_1971_b1
|
theorem putnam_1971_b1
(S : Type*) [Mul S]
(hself : β x : S, x * x = x)
(h2 : β x y z : S, (x * y) * z = (y * z) * x)
: (β x y z : S, (x * y) * z = x * (y * z)) β§ (β x y : S, x * y = y * x) :=
sorry
|
922a95598124c41a
|
putnam_2016_b4
|
abbrev putnam_2016_b4_solution : β β β := sorry
-- (fun n : β => (2 * n)! / (4 ^ n * (n)!))
/--
Let $A$ be a $2n \times 2n$ matrix, with entries chosen independently at random. Every entry is chosen to be $0$ or $1$, each with probability $1/2$. Find the expected value of $\det(A-A^t)$ (as a function of $n$), where $A^t$ is the transpose of $A$.
-/
theorem putnam_2016_b4
(n : β) (npos : n β₯ 1)
(mats01 : Set (Matrix (Fin (2 * n)) (Fin (2 * n)) β))
(hmats01 : mats01 = {A | β i j : Fin (2 * n), A i j = 0 β¨ A i j = 1}) :
(β' A : mats01, (A.1 - (Matrix.transpose A)).det) / mats01.ncard = putnam_2016_b4_solution n :=
sorry
|
e6e5a8688794d903
|
putnam_2006_b4
|
abbrev putnam_2006_b4_solution : β β β := sorry
-- fun k β¦ 2 ^ k
/--
Let $Z$ denote the set of points in $\mathbb{R}^n$ whose coordinates are $0$ or $1$. (Thus $Z$ has $2^n$ elements, which are the vertices of a unit hypercube in $\mathbb{R}^n$.) Given a vector subspace $V$ of $\mathbb{R}^n$, let $Z(V)$ denote the number of members of $Z$ that lie in $V$. Let $k$ be given, $0 \leq k \leq n$. Find the maximum, over all vector subspaces $V \subseteq \mathbb{R}^n$ of dimension $k$, of the number of points in $V \cap Z$.
-/
theorem putnam_2006_b4
(n k : β)
(npos : n > 0)
(hk : k β€ n)
(Z : Set (Fin n β β))
(hZ : Z = {P : Fin n β β | β j : Fin n, P j = 0 β¨ P j = 1}) :
IsGreatest
{y | β V : Subspace β (Fin n β β), Module.rank β V = k β§ (Z β© V).ncard = y}
(putnam_2006_b4_solution k) :=
sorry
|
dbe94be1a48a57ac
|
putnam_1976_b5
|
abbrev putnam_1976_b5_solution : β β Polynomial β€ := sorry
-- fun n => C (Nat.factorial n)
/--
Find $$\sum_{k=0}^{n} (-1)^k {n \choose k} (x - k)^n.$$
-/
theorem putnam_1976_b5
: β n : β, β k in Finset.range (n + 1), C ((-(1 : β€))^k * Nat.choose n k) * (X - (C (k : β€)))^n = putnam_1976_b5_solution n :=
sorry
|
a82bb6ac6dc0eb89
|
putnam_1966_b5
|
theorem putnam_1966_b5
(S : Finset (EuclideanSpace β (Fin 2)))
(hcard : S.card β₯ 3)
(hS : β s β S, s.card = 3 β Β¬Collinear β s.toSet)
: β L : ZMod S.card β (EuclideanSpace β (Fin 2)), (β p β S, β! i : ZMod S.card, p = L i) β§
β i j : ZMod S.card, i β j β (β I : EuclideanSpace β (Fin 2),
(I β segment β (L i) (L (i + 1)) β§ I β segment β (L j) (L (j + 1))) β
I = L i β¨ I = L (i + 1) β¨ I = L j β¨ I = L (j + 1)) :=
sorry
|
ed5d5598b7362eb1
|
putnam_2023_a4
|
theorem putnam_2023_a4
(v : Fin 12 β EuclideanSpace β (Fin 3))
(hv :
letI Ο : β := (1 + β5) / 2
letI e : (Fin 3 β β) β EuclideanSpace β (Fin 3) := (WithLp.equiv _ _).symm
letI s := β(1 + Ο ^ 2)
β g : EuclideanSpace β (Fin 3) ββα΅’[β] EuclideanSpace β (Fin 3),
g β v = sβ»ΒΉ β’ e β ![![1, Ο, 0], ![-1, Ο, 0], ![ 1, -Ο, 0], ![-1, -Ο, 0],
![Ο, 0, 1], ![ Ο, 0, -1], ![-Ο, 0, 1], ![-Ο, 0, -1],
![0, 1, Ο], ![ 0, -1, Ο], ![ 0, 1, -Ο], ![ 0, -1, -Ο]])
(w : EuclideanSpace β (Fin 3))
(Ξ΅ : β) (hΞ΅ : Ξ΅ > 0) :
β a : Fin 12 β β€, ββ i, a i β’ v i - wβ < Ξ΅ :=
sorry
|
2e9a705d5040e3bb
|
putnam_1969_a6
|
theorem putnam_1969_a6
(x : β β β)
(y : β β β)
(hy1 : β n β₯ 2, y n = x (n-1) + 2 * (x n))
(hy2 : β c : β, Tendsto y atTop (π c))
: β C : β, Tendsto x atTop (π C) :=
sorry
|
8eb86142cbe439a0
|
putnam_1979_a6
|
theorem putnam_1979_a6
(n : β)
(p : β β β)
(hp : β i β Finset.range n, p i β Icc 0 1)
: β x β Icc 0 1, (β i β Finset.range n, x β p i) β§ β i in Finset.range n, 1/|x - p i| β€ 8*n*β i in Finset.range n, (1 : β)/(2*i + 1) :=
sorry
|
bf182b3f0c78cd2b
|
putnam_1987_b6
|
theorem putnam_1987_b6
(p : β)
(F : Type*) [Field F] [Fintype F]
(S : Set F)
(hp : Odd p β§ Nat.Prime p)
(Fcard : Fintype.card F = p ^ 2)
(Snz : β x β S, x β 0)
(Scard : S.ncard = ((p : β€) ^ 2 - 1) / 2)
(hS : β a : F, a β 0 β Xor' (a β S) (-a β S)) :
(Even ((S β© {x | β a β S, x = 2 * a}).ncard)) :=
sorry
|
0ab58e1c5ffe2a39
|
putnam_2020_a2
|
abbrev putnam_2020_a2_solution : β β β := sorry
-- fun k β¦ 4 ^ k
/--
Let $k$ be a nonnegative integer. Evaluate
\[
\sum_{j=0}^k 2^{k-j} \binom{k+j}{j}.
\]
-/
theorem putnam_2020_a2
(k : β)
: (β j in Finset.Icc 0 k, 2 ^ (k - j) * Nat.choose (k + j) j = putnam_2020_a2_solution k) :=
sorry
|
1ef22069305e95b4
|
putnam_1988_a5
|
theorem putnam_1988_a5
: (β f : β β β, (β x > 0, f (f x) = 6 * x - f x β§ f x > 0) β§ (β g : β β β, (β x > 0, g (g x) = 6 * x - g x β§ g x > 0) β (β x > 0, f x = g x))) :=
sorry
|
3458e2dd6ece982e
|
putnam_1965_b3
|
theorem putnam_1965_b3
: {(a, b, c) : β€ Γ β€ Γ β€ | a > 0 β§ a β€ b β§ c > 0 β§ a^2 + b^2 = c^2 β§ a*b/(2 : β) = 2*(a + b + c)}.ncard = 3 :=
sorry
|
be013e20faf74bd4
|
putnam_1998_a5
|
theorem putnam_1998_a5
(k : β)
(c : Fin k β (EuclideanSpace β (Fin 2)))
(r : Fin k β β)
(hr : β i, r i > 0)
(E : Set (EuclideanSpace β (Fin 2)))
(hE : E β β i, ball (c i) (r i)) :
β (n : β) (t : Fin n β Fin k),
(β i j, i β j β (ball (c (t i)) (r (t i)) β© ball (c (t j)) (r (t j)) = β
)) β§
E β β i : Fin n, ball (c (t i)) (3 * (r (t i))) :=
sorry
|
3df95b52b64d12ec
|
putnam_1975_b3
|
abbrev putnam_1975_b3_solution : β β β := sorry
-- fun k : β => 1/(Nat.factorial k)
/--
Let $s_k (a_1, a_2, \dots, a_n)$ denote the $k$-th elementary symmetric function; that is, the sum of all $k$-fold products of the $a_i$. For example, $s_1 (a_1, \dots, a_n) = \sum_{i=1}^{n} a_i$, and $s_2 (a_1, a_2, a_3) = a_1a_2 + a_2a_3 + a_1a_3$. Find the supremum $M_k$ (which is never attained) of $$\frac{s_k (a_1, a_2, \dots, a_n)}{(s_1 (a_1, a_2, \dots, a_n))^k}$$ across all $n$-tuples $(a_1, a_2, \dots, a_n)$ of positive real numbers with $n \ge k$.
-/
theorem putnam_1975_b3
: β k : β, k > 0 β (β a : Multiset β, (β i β a, i > 0) β§ card a β₯ k β
(esymm a k)/(esymm a 1)^k β€ putnam_1975_b3_solution k) β§
β M : β, M < putnam_1975_b3_solution k β (β a : Multiset β, (β i β a, i > 0) β§ card a β₯ k β§
(esymm a k)/(esymm a 1)^k > M) :=
sorry
|
f9d18916e89daae1
|
putnam_2002_b6
|
theorem putnam_2002_b6
(p : β)
(hp : Nat.Prime p)
(M : Matrix (Fin 3) (Fin 3) (MvPolynomial (Fin 3) β€))
(hM : M = fun (r c : Fin 3) => ((X c)^(p^(r : β)) : MvPolynomial (Fin 3) β€))
(cong : β β MvPolynomial (Fin 3) β€ Γ MvPolynomial (Fin 3) β€ β Prop)
(hcong : cong = fun p : β => fun (f, g) => β n : Fin 3 ββ β, Int.ModEq p (f.coeff n) (g.coeff n))
: β S : Finset (MvPolynomial (Fin 3) β€), cong p ((det M), (β s in S, s)) β§ β s β S, (β a b c : β€, s = (C a)*(X 0) + (C b)*(X 1) + (C c)*(X 2)) :=
sorry
|
4a84e27500e71e6b
|
putnam_2012_b6
|
theorem putnam_2012_b6
(p : β)
(hpodd : Odd p)
(hpprime : Nat.Prime p)
(hpmod3 : p β‘ 2 [MOD 3])
(P : Equiv.Perm (Fin p))
(hP : β i : Fin p, P i = (i * i * i))
: Equiv.Perm.signAux P = 1 β (p β‘ 3 [MOD 4]) :=
sorry
|
b7edc025afdf52f8
|
putnam_2005_b2
|
abbrev putnam_2005_b2_solution : Set (β Γ (β β β€)) := sorry
-- {(n, k) : β Γ (β β β€) | (n = 1 β§ k 0 = 1) β¨ (n = 3 β§ (k '' {0, 1, 2} = {2, 3, 6})) β¨ (n = 4 β§ (β i : Fin 4, k i = 4))}
/--
Find all positive integers $n,k_1,\dots,k_n$ such that $k_1+\cdots+k_n=5n-4$ and $\frac{1}{k_1}+\cdots+\frac{1}{k_n}=1$.
-/
theorem putnam_2005_b2
: {((n : β), (k : β β β€)) | (n > 0) β§ (β i β Finset.range n, k i > 0) β§ (β i in Finset.range n, k i = 5 * n - 4) β§ (β i : Finset.range n, (1 : β) / (k i) = 1)} = putnam_2005_b2_solution :=
sorry
|
541be56cee7e74bd
|
putnam_2015_b2
|
abbrev putnam_2015_b2_solution : Prop := sorry
-- True
/--
Given a list of the positive integers $1,2,3,4,\dots$, take the first three numbers $1,2,3$ and their sum $6$ and cross all four numbers off the list. Repeat with the three smallest remaining numbers $4,5,7$ and their sum $16$. Continue in this way, crossing off the three smallest remaining numbers and their sum, and consider the sequence of sums produced: $6,16,27,36,\dots$. Prove or disprove that there is some number in the sequence whose base $10$ representation ends with $2015$.
-/
theorem putnam_2015_b2
(sets : β β Set β)
(Smin3 : Set β β (Fin 3 β β))
(sums : β β β)
(hsets0 : sets 0 = Set.Ici 1)
(hmin3 : β S : Set β, S.encard β₯ 3 β ((Smin3 S) 0 = sInf S β§ (Smin3 S) 1 = sInf (S \ {(Smin3 S) 0}) β§ (Smin3 S) 2 = sInf (S \ {(Smin3 S) 0, (Smin3 S) 1})))
(hsums : β n : β, sums n = (Smin3 (sets n)) 0 + (Smin3 (sets n)) 1 + (Smin3 (sets n)) 2)
(hsetsn : β n : β, sets (n + 1) = sets n \ {(Smin3 (sets n)) 0, (Smin3 (sets n)) 1, (Smin3 (sets n)) 2, sums n})
: (β n : β, List.IsPrefix [5, 1, 0, 2] (Nat.digits 10 (sums n))) β putnam_2015_b2_solution :=
sorry
|
d864ebc2a87941c3
|
putnam_1990_b2
|
theorem putnam_1990_b2
(x z : β)
(P : β β β)
(xlt1 : |x| < 1)
(zgt1 : |z| > 1)
(hP : β j β₯ 1, P j = (β i : Fin j, (1 - z * x ^ (i : β))) / (β i : Set.Icc 1 j, (z - x ^ (i : β))))
: 1 + (β' j : Set.Ici 1, (1 + x ^ (j : β)) * P j) = 0 :=
sorry
|
56940edcec029257
|
putnam_1990_b3
|
theorem putnam_1990_b3
(S : Set (Matrix (Fin 2) (Fin 2) β))
(hS : β A β S, β i j : Fin 2, (β x : β€, A i j = x ^ 2) β§ A i j β€ 200)
: (S.encard > 50387) β (β A β S, β B β S, A β B β§ A * B = B * A) :=
sorry
|
6107e065fee0cda4
|
putnam_1980_b3
|
abbrev putnam_1980_b3_solution : Set β := sorry
-- {a : β | a β₯ 3}
/--
For which real numbers $a$ does the sequence defined by the initial condition $u_0=a$ and the recursion $u_{n+1}=2u_n-n^2$ have $u_n>0$ for all $n \geq 0$? (Express the answer in the simplest form.)
-/
theorem putnam_1980_b3
(a : β)
(u : β β β)
(hu : u 0 = a β§ (β n : β, u (n + 1) = 2 * u n - n ^ 2))
: (β n : β, u n > 0) β a β putnam_1980_b3_solution :=
sorry
|
e87144efaee76557
|
putnam_1962_b6
|
theorem putnam_1962_b6
(n : β)
(a b : β β β)
(xs : Set β)
(f : β β β)
(hf : f = fun x : β => β k in Finset.Icc 0 n, ((a k) * Real.sin (k * x) + (b k) * Real.cos (k * x)))
(hf1 : β x β Set.Icc 0 (2 * Ο), |f x| β€ 1)
(hxs : xs.ncard = 2 * n β§ xs β Set.Ico 0 (2 * Ο))
(hfxs : β x β xs, |f x| = 1)
: (Β¬β c : β, f = fun x : β => c) β β a : β, f = fun x : β => Real.cos (n * x + a) :=
sorry
|
60ddd286fd96ba25
|
putnam_1972_b6
|
theorem putnam_1972_b6
(k : β)
(hk : k β₯ 1)
(n : Fin k β β€)
(hn : β i : Fin k, n i > 0)
(hn' : β i j : Fin k, i < j β n i < n j)
(zpoly : β β β)
(hzpoly : zpoly = fun z => 1 + β i : Fin k, z^(n i))
: β z : β, z β ball 0 ((Real.sqrt 5 - 1)/2) β zpoly z β 0 :=
sorry
|
943d2293ffaabc84
|
putnam_2005_b3
|
abbrev putnam_2005_b3_solution : Set (β β β) := sorry
-- {f : β β β | βα΅ (c > 0) (d > (0 : β)), (d = 1 β c = 1) β§ (Ioi 0).EqOn f (fun x β¦ c * x ^ d)}
/--
Find all differentiable functions $f:(0,\infty) \to (0,\infty)$ for which there is a positive real number $a$ such that $f'(\frac{a}{x})=\frac{x}{f(x)}$ for all $x>0$.
-/
theorem putnam_2005_b3
(f : β β β)
(hf : β x > 0, 0 < f x)
(hf' : DifferentiableOn β f (Ioi 0)) :
(β a > 0, β x > 0, deriv f (a / x) = x / f x) β f β putnam_2005_b3_solution :=
sorry
|
f82a45083cc0a5ec
|
putnam_2015_b3
|
abbrev putnam_2015_b3_solution : Set (Matrix (Fin 2) (Fin 2) β) := sorry
-- {A : Matrix (Fin 2) (Fin 2) β | (β Ξ± : β, β i j : Fin 2, A i j = Ξ± * 1) β¨ (β Ξ² : β, A 0 0 = Ξ² * -3 β§ A 0 1 = Ξ² * -1 β§ A 1 0 = Ξ² * 1 β§ A 1 1 = Ξ² * 3)}
/--
Let $S$ be the set of all $2 \times 2$ real matrices $M=\begin{pmatrix} a & b \\ c & d \end{pmatrix}$ whose entries $a,b,c,d$ (in that order) form an arithmetic progression. Find all matrices $M$ in $S$ for which there is some integer $k>1$ such that $M^k$ is also in $S$.
-/
theorem putnam_2015_b3
(M : Matrix (Fin 2) (Fin 2) β)
(S : Set (Matrix (Fin 2) (Fin 2) β))
(hS : S = {M' | (M' 0 1 - M' 0 0 = M' 1 0 - M' 0 1) β§ (M' 1 0 - M' 0 1 = M' 1 1 - M' 1 0)}) :
(M β S β§ (β k > 1, M ^ k β S)) β M β putnam_2015_b3_solution :=
sorry
|
3784e91d14e96e27
|
putnam_2020_a3
|
abbrev putnam_2020_a3_solution : Prop := sorry
-- False
/--
Let $a_0 = \pi/2$, and let $a_n = \sin(a_{n-1})$ for $n \geq 1$. Determine whether
\[
\sum_{n=1}^\infty a_n^2
\]
converges.
-/
theorem putnam_2020_a3
(a : β β β)
(ha0 : a 0 = Real.pi / 2)
(ha : β n, a (n+1) = Real.sin (a n)) :
(β L, Tendsto (fun m : β => β n in Finset.Icc 1 m, (a n)^2) atTop (π L)) β putnam_2020_a3_solution :=
sorry
|
0ce6b920dbf938a6
|
putnam_1988_a4
|
abbrev putnam_1988_a4_solution : Prop Γ Prop := sorry
-- (True, False)
/--
\begin{enumerate}
\item[(a)] If every point of the plane is painted one of three colors, do there necessarily exist two points of the same color exactly one inch apart?
\item[(b)] What if ``three'' is replaced by ``nine''?
\end{enumerate}
-/
theorem putnam_1988_a4
(p : β β Prop)
(hp : β n, p n β
β color : (EuclideanSpace β (Fin 2)) β Fin n,
β p q : EuclideanSpace β (Fin 2),
color p = color q β§ dist p q = 1) :
(let (a, b) := putnam_1988_a4_solution; (p 3 β a) β§ (p 9 β b)) :=
sorry
|
4b364f7bd5af11f0
|
putnam_1965_b2
|
theorem putnam_1965_b2
(n : β)
(hn : n > 1)
(won : Fin n β Fin n β Bool)
(hirrefl : β i : Fin n, won i i = false)
(hantisymm : β i j : Fin n, i β j β won i j = Β¬won j i)
(w l : Fin n β β€)
(hw : w = fun r : Fin n => β j : Fin n, (if won r j then 1 else 0))
(hl : l = fun r : Fin n => n - 1 - w r)
: β r : Fin n, (w r)^2 = β r : Fin n, (l r)^2 :=
sorry
|
e84e8f7f87a75127
|
putnam_1998_a4
|
abbrev putnam_1998_a4_solution : Set β := sorry
-- {n | n β‘ 1 [MOD 6]}
/--
Let $A_1=0$ and $A_2=1$. For $n>2$, the number $A_n$ is defined by concatenating the decimal expansions of $A_{n-1}$ and $A_{n-2}$ from left to right. For example $A_3=A_2 A_1=10$, $A_4=A_3 A_2 = 101$, $A_5=A_4 A_3 = 10110$, and so forth. Determine all $n$ such that $11$ divides $A_n$.
-/
theorem putnam_1998_a4
(A : β β List β)
(hA1 : A 1 = [0])
(hA2 : A 2 = [1])
(hA : β n > 0, A (n + 2) = A (n + 1) ++ A n) :
{n | 1 β€ n β§ 11 β£ Nat.ofDigits 10 (A n).reverse} = putnam_1998_a4_solution :=
sorry
|
949d86cd8f357b64
|
putnam_1975_b2
|
theorem putnam_1975_b2
(slab : (Fin 3 β β) β β β β β Set (Fin 3 β β))
(hslab : slab = fun normal offset thickness => {x : Fin 3 β β | offset < normal β¬α΅₯ x β§ normal β¬α΅₯ x < offset + thickness})
(normals : β β (Fin 3 β β))
(offsets : β β β)
(thicknesses : β β β)
(hnormalsunit : β i : β, βnormals iβ = 1)
(hthicknessespos : β i : β, thicknesses i > 0)
(hthicknessesconv : β C : β, Tendsto (fun i : β => β j in Finset.range i, thicknesses j) atTop (π C))
: Set.univ β β i : β, slab (normals i) (offsets i) (thicknesses i) :=
sorry
|
163367837a1b1d37
|
putnam_1984_b1
|
abbrev putnam_1984_b1_solution : Polynomial β Γ Polynomial β := sorry
-- (Polynomial.X + 3, -Polynomial.X - 2)
/--
Let $n$ be a positive integer, and define $f(n)=1!+2!+\dots+n!$. Find polynomials $P(x)$ and $Q(x)$ such that $f(n+2)=P(n)f(n+1)+Q(n)f(n)$ for all $n \geq 1$.
-/
theorem putnam_1984_b1
(f : β β β€)
(hf : β n > 0, f n = β i : Set.Icc 1 n, ((i)! : β€))
: let (P, Q) := putnam_1984_b1_solution; β n β₯ 1, f (n + 2) = P.eval (n : β) * f (n + 1) + Q.eval (n : β) * f n :=
sorry
|
1e4584208b10a382
|
putnam_1994_b1
|
abbrev putnam_1994_b1_solution : Set β€ := sorry
-- {n : β€ | (315 β€ n β§ n β€ 325) β¨ (332 β€ n β§ n β€ 350)}
/--
Find all positive integers $n$ that are within $250$ of exactly $15$ perfect squares.
-/
theorem putnam_1994_b1
(n : β€) :
n β putnam_1994_b1_solution β
(0 < n β§ {m : β | |n - m ^ 2| β€ 250}.encard = 15) :=
sorry
|
c66416b6c99cab31
|
putnam_1966_b4
|
theorem putnam_1966_b4
(m n : β)
(S : Finset β)
(hS : (β i β S, i > 0) β§ S.card = m * n + 1)
: β T β S, (T.card = m + 1 β§ β j β T, β i β T, i β j β Β¬(j β£ i)) β¨ (T.card = n + 1 β§ β i β T, β j β T, j < i β j β£ i) :=
sorry
|
4f2bef71963f2ff8
|
putnam_2023_a5
|
abbrev putnam_2023_a5_solution : Set β := sorry
-- {-(3^1010 - 1)/2, -(3^1010 - 1)/2 + Real.sqrt (9^1010 - 1) * Complex.I/4, -(3^1010 - 1)/2 - Real.sqrt (9^1010 - 1) * Complex.I/4}
/--
For a nonnegative integer $k$, let $f(k)$ be the number of ones in the base 3 representation of $k$. Find all complex numbers $z$ such that \[ \sum_{k=0}^{3^{1010}-1} (-2)^{f(k)} (z+k)^{2023} = 0. \]
-/
theorem putnam_2023_a5
: {z : β | β k in Finset.Icc 0 (3^1010 - 1), (-2)^(num_ones (digits 3 k)) * (z + k)^2023 = 0} = putnam_2023_a5_solution :=
sorry
|
1f2ca5db45acbbc5
|
putnam_2011_b1
|
theorem putnam_2011_b1
(h k : β€)
(hkpos : h > 0 β§ k > 0)
: β Ξ΅ > 0, β m n : β€, m > 0 β§ n > 0 β§ Ξ΅ < |h * Real.sqrt m - k * Real.sqrt n| β§ |h * Real.sqrt m - k * Real.sqrt n| < 2 * Ξ΅ :=
sorry
|
66815d046dd27714
|
putnam_2001_b1
|
theorem putnam_2001_b1
(n : β)
(hn : n > 0) (hn' : Even n)
(nums : Fin n β Fin n β β€)
(colors : Fin n β Fin n β Fin 2)
(hnums : β k l, nums k l = k * n + l + 1)
(hcolorsrows : β k, (β l, (if (colors k l = 0) then 1 else 0)) = n / 2)
(hcolorscols : β l, (β k, (if (colors k l = 0) then 1 else 0)) = n / 2) :
(β k, β l, (if (colors k l = 0) then (nums k l) else 0)) = (β k, β l, (if (colors k l = 1) then (nums k l) else 0)) :=
sorry
|
cd5f365a9654ac4f
|
putnam_2024_a1
|
abbrev putnam_2024_a1_solution : Set β := sorry
--{1}
/--
Determine all positive integers $n$ for which there exist positive integers $a$, $b$ and $c$ satisfying $2a^n + 3b^n = 4c^n$.
-/
theorem putnam_2024_a1 :
{n : β | 0 < n β§ β (a b c : β), 0 < a β§ 0 < b β§ 0 < c β§ 2*a^n + 3*b^n = 4*c^n}
= putnam_2024_a1_solution :=
sorry
|
f87967b5a731b7df
|
putnam_2016_b5
|
abbrev putnam_2016_b5_solution : Set (Set.Ioi (1 : β) β Set.Ioi (1 : β)) := sorry
-- {f : Set.Ioi (1 : β) β Set.Ioi (1 : β) | β c : β, c > 0 β§ β x : Set.Ioi (1 : β), (f x : β) = x ^ c}
/--
Find all functions $f$ from the interval $(1,\infty)$ to $(1,\infty)$ with the following property: if $x,y \in (1,\infty)$ and $x^2 \leq y \leq x^3$, then $(f(x))^2 \leq f(y) \leq (f(x))^3$.
-/
theorem putnam_2016_b5
(f : Set.Ioi (1 : β) β Set.Ioi (1 : β)) :
f β putnam_2016_b5_solution β
(β x y : Set.Ioi (1 : β), ((x : β) ^ 2 β€ y β§ y β€ (x : β) ^ 3) β ((f x : β) ^ 2 β€ f y β§ f y β€ (f x : β) ^ 3)) :=
sorry
|
2f294b010e3f9a5e
|
putnam_2006_b5
|
abbrev putnam_2006_b5_solution : β := sorry
-- 1 / 16
/--
For each continuous function $f: [0,1] \to \mathbb{R}$, let $I(f) = \int_0^1 x^2 f(x)\,dx$ and $J(x) = \int_0^1 x \left(f(x)\right)^2\,dx$. Find the maximum value of $I(f) - J(f)$ over all such functions $f$.
-/
theorem putnam_2006_b5
(I J : (β β β) β β)
(hI : I = fun f β¦ β« x in (0)..1, x ^ 2 * (f x))
(hJ : J = fun f β¦ β« x in (0)..1, x * (f x) ^ 2) :
IsGreatest
{y | β f : β β β, ContinuousOn f (Icc 0 1) β§ I f - J f = y}
putnam_2006_b5_solution :=
sorry
|
1cb77bdbebeb4c00
|
putnam_1983_b5
|
abbrev putnam_1983_b5_solution : β := sorry
-- log (4 / Real.pi)
/--
Define $\left\lVert x \right\rVert$ as the distance from $x$ to the nearest integer. Find $\lim_{n \to \infty} \frac{1}{n} \int_{1}^{n} \left\lVert \frac{n}{x} \right\rVert \, dx$. You may assume that $\prod_{n=1}^{\infty} \frac{2n}{(2n-1)} \cdot \frac{2n}{(2n+1)} = \frac{\pi}{2}$.
-/
theorem putnam_1983_b5
(dist_fun : β β β)
(hdist_fun : dist_fun = fun (x : β) β¦ min (x - βxβ) (βxβ - x))
(fact : Tendsto (fun N β¦ β n in Finset.Icc 1 N, (2 * n / (2 * n - 1)) * (2 * n / (2 * n + 1)) : β β β) atTop (π (Real.pi / 2)))
: (Tendsto (fun n β¦ (1 / n) * β« x in (1)..n, dist_fun (n / x) : β β β) atTop (π putnam_1983_b5_solution)) :=
sorry
|
fbf624b8930b6dcd
|
putnam_1993_b5:
|
theorem putnam_1993_b5:
Β¬β p : Fin 4 β (EuclideanSpace β (Fin 2)),
β i j, i β j β
(β n : β€, dist (p i) (p j) = n β§ Odd n) :=
sorry
|
35326c51997420cb
|
putnam_2019_a6
|
theorem putnam_2019_a6
(g : β β β)
(r : β)
(hcont : ContinuousOn g (Set.Icc 0 1))
(hdiff : ContDiffOn β 1 g (Set.Ioo 0 1) β§ DifferentiableOn β (deriv g) (Set.Ioo 0 1))
(hr : r > 1)
(hlim : Tendsto (fun x => g x / x ^ r) (π[>] 0) (π 0))
: (Tendsto (deriv g) (π[>] 0) (π 0)) β¨ (Tendsto (fun x : β => sSup {x' ^ r * abs (iteratedDeriv 2 g x') | x' β Set.Ioc 0 x}) (π[>] 0) atTop) :=
sorry
|
e5e76acaf00ea014
|
putnam_1967_b5
|
theorem putnam_1967_b5
(n : β)
(hn : n > 0)
: (1 : β)/2 = β i in Finset.range n, (Nat.choose (n + i - 1) i) * (2 : β)^(-(n : β€) - i) :=
sorry
|
daa39e24318255c9
|
putnam_1977_b5
|
theorem putnam_1977_b5
(n : β)
(hn : n > 1)
(a : Fin n β β)
(A : β)
(hA : A + β i : Fin n, (a i)^2 < (1/((n : β) - 1))*(β i : Fin n, a i)^2)
: β i j : Fin n, i < j β A < 2*(a i)*(a j) :=
sorry
|
0a8f12b4dcf0b46f
|
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