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
mod = 998244353

n = ii()

dp = [[[0] * 3 for _ in range(n // 3 + 2)] for _ in range(n + 1)]

dp[0][0][0] = 1

for i in range(n):
    for j in range(n // 3 + 1):
        for k in range(3):
            if k < 2:
                dp[i + 1][j][(k + 1) % 3] += dp[i][j][k]
            dp[i + 1][j][k] += 25 * dp[i][j][k]
            dp[i + 1][j][k] %= mod
            dp[i + 1][j][(k + 1) % 3] %= mod
        dp[i + 1][j + 1][0] += dp[i][j][k]
        dp[i + 1][j + 1][0] %= mod
ans = 0
for i in range(n//3 + 1):
    for j in range(3):
        ans += i * dp[n][i][j]
        ans %= mod
print(ans)