#include<bits/stdc++.h>
using namespace std;
#define rep(i,n) for (long long i=0;i<(long long)(n);i++)
#define all(v) v.begin(),v.end()
using ll=long long;
using pll=pair<ll,ll>;
using tll=tuple<ll,ll,ll>;
const ll INF=(1ll<<60);
template<class T> void chmin(T &a,T b){
    if(a>b){
        a=b;
    }
}
template<class T> void chmax(T &a,T b){
    if(a<b){
        a=b;
    }
}
int main(){
    const ll mod=998244353;
    ll n;
    cin >> n;
    vector<vector<ll>> dp(n+1,vector<ll>(n+1,0));
    dp[0][0]=1;
    rep(i,n){
        rep(j,n){
            if(dp[i][j]==0) continue;
            dp[i+1][j]+=25*dp[i][j];
            dp[i+1][j]%=mod;
            dp[i+1][j+1]+=dp[i][j];
            dp[i+1][j+1]%=mod;
        }
    }
    ll ans=0;
    rep(j,n+1){
        ans+=j/3*dp[n][j];
        ans%=mod;
    }
    cout << ans << endl;
}