#include <bits/stdc++.h>
using namespace std;
const long long MOD = 998244353;
int main(){
  int N, K;
  cin >> N >> K;
  vector<long long> inv(N + 1);
  inv[1] = 1;
  for (int i = 2; i <= N; i++){
    inv[i] = MOD - inv[MOD % i] * (MOD / i) % MOD;
  }
  vector<vector<long long>> dp(K + 1, vector<long long>(K + 1, 0));
  dp[0][0] = 1;
  for (int i = 0; i < K; i++){
    for (int j = 0; j < K; j++){
      if (dp[i][j] > 0){
        int c = i - j * 2;
        dp[i + 1][j] += dp[i][j] * (N - c) % MOD * inv[N] % MOD;
        dp[i + 1][j] %= MOD;
        dp[i + 1][j + 1] += dp[i][j] * c % MOD * inv[N] % MOD;
        dp[i + 1][j + 1] %= MOD;
      }
    }
  }
  long long ans = 0;
  for (int i = 0; i <= K; i++){
    ans += dp[K][i] * (N + i) % MOD;
  }
  ans %= MOD;
  cout << ans << endl;
}