import sys def calc(n): result =0 for i in range(1,n+1): result += sum([j for j in range(1,i+1)]) return result for line in sys.stdin: a = line.strip() print(calc(int(a)))
n = int(input()) s = 0 for i in range(1,n+1): if i%2 == 0: s += (i//2+1)*i-i//2 else: s += (i//2+1)*i print(s)
n = int(input()) s = 0 for i in range(1,n+1): s += (i//2+1)*i + i//2*(i%2-1) print(s)