#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<long long> dp(K + 1, 0);
  dp[0] = 0;
  for (int i = 0; i < K; i++){
    dp[i + 1] = dp[i] + (MOD + i - 2 * dp[i] % MOD) * inv[N];
    dp[i + 1] %= MOD;
  }
  cout << (N + dp[K]) % MOD << endl;
}