import sys
from collections import deque, Counter
sys.setrecursionlimit(5 * 10 ** 5)
from pypyjit import set_param
set_param('max_unroll_recursion=-1')
input = lambda: sys.stdin.readline().rstrip()
ii = lambda: int(input())
mi = lambda: map(int, input().split())
li = lambda: list(mi())
inf = 2 ** 63 - 1

n = ii()
ans = 0
for i in range(1, n + 1):
    if i % 3 == 0:
        ans += i ** 3
    if i % 3 == 1:
        ans += i ** 1
    if i % 3 == 2:
        ans += i ** 2
print(ans)