from typing import List, Tuple, Callable, TypeVar
import sys
import itertools
import heapq
import bisect
import math
from collections import deque, defaultdict, Counter
from functools import lru_cache, cmp_to_key

input = sys.stdin.readline

if __file__ != 'prog.py':
    sys.setrecursionlimit(10 ** 6)


def readints(): return map(int, input().split())
def readlist(): return list(readints())
def readstr(): return input()[:-1]


N = int(input())
mod = 998244353

dp = [0] * (N + 1)
dp[0] = 1
for _ in range(N):
    ndp = [0] * (N + 1)
    for j in range(N + 1):
        if j:
            ndp[j] += dp[j - 1]
        ndp[j] += 25 * dp[j]
        ndp[j] %= mod
    dp = ndp
ans = 0
for i in range(N + 1):
    ans += (i // 3) * dp[i]
    ans %= mod
print(ans)