n=int(input(""))

total=0
for t in range(2,int(n/2)+2):
	d=n
	c=0
	x=t

	
	while(d-x>0):
		if(x<=0 or d<=0):
			break
		
		
		if(d%2==0):
			
			if(d-x-1<=0):
				
				d=d-1
				
			else:
				d=d-1
				c=c+1
				#print(d+1,x)
				
		else:
			d=d-1
			c=c+1
			#print(d+1,x)
		if(d-x==0):
			x=x-2
			d=n
			
	
	
	total=total+c*t
	#print(total)
print(total+n)
e8fc394169415c0036571800f34cd070354ebcc8
<mask token>

<mask token>
for t in range(2, int(n / 2) + 2):
    d = n
    c = 0
    x = t
    while d - x > 0:
        if x <= 0 or d <= 0:
            break
        if d % 2 == 0:
            if d - x - 1 <= 0:
                d = d - 1
            else:
                d = d - 1
                c = c + 1
        else:
            d = d - 1
            c = c + 1
        if d - x == 0:
            x = x - 2
            d = n
    total = total + c * t
print(total + n)

n = int(input(''))
total = 0
for t in range(2, int(n / 2) + 2):
    d = n
    c = 0
    x = t
    while d - x > 0:
        if x <= 0 or d <= 0:
            break
        if d % 2 == 0:
            if d - x - 1 <= 0:
                d = d - 1
            else:
                d = d - 1
                c = c + 1
        else:
            d = d - 1
            c = c + 1
        if d - x == 0:
            x = x - 2
            d = n
    total = total + c * t
print(total + n)

n=int(input(""))

total=0
for t in range(2,int(n/2)+2):
	d=n
	c=0
	x=t

	
	while(d-x>0):
		if(x<=0 or d<=0):
			break
		
		
		if(d%2==0):
			
			if(d-x-1<=0):
				
				d=d-1
				
			else:
				d=d-1
				c=c+1
				#print(d+1,x)
				
		else:
			d=d-1
			c=c+1
			#print(d+1,x)
		if(d-x==0):
			x=x-2
			d=n
			
	
	
	total=total+c*t
	#print(total)
print(total+n)