#include<bits/stdc++.h>
#include<atcoder/all>
#define rep(i,n) for(int i=0;i<n;i++)
using namespace std;
using namespace atcoder;
typedef long long ll;
typedef vector<int> vi;
typedef vector<long long> vl;
typedef vector<vector<int>> vvi;
typedef vector<vector<long long>> vvl;
typedef long double ld;
typedef pair<int, int> P;

ostream& operator<<(ostream& os, const modint& a) {os << a.val(); return os;}
template <int m> ostream& operator<<(ostream& os, const static_modint<m>& a) {os << a.val(); return os;}
template<typename T> istream& operator>>(istream& is, vector<T>& v){int n = v.size(); assert(n > 0); rep(i, n) is >> v[i]; return is;}
template<typename U, typename T> ostream& operator<<(ostream& os, const pair<U, T>& p){os << p.first << ' ' << p.second << "\n"; return os;}
template<typename T> ostream& operator<<(ostream& os, const vector<T>& v){int n = v.size(); rep(i, n) os << v[i] << (i == n - 1 ? "\n" : " "); return os;}
template <typename T> ostream& operator<<(ostream& os, const vector<vector<T>>& v){int n = v.size(); rep(i, n) os << v[i] << (i == n - 1 ? "\n" : ""); return os;}

using mint = modint998244353;

int main(){
	int n, k;
	cin >> n >> k;
	vector<mint> dp(n + 1);
	dp[0] = 1;
	mint ans = 0;
	mint rev = mint(1) / n;
	rep(_, k){
		vector<mint> dp_old(n + 1);
		swap(dp, dp_old);
		rep(i, n + 1){
			if(i > 0){
				mint plus = dp_old[i] * i * rev;
				dp[i - 1] += plus;
				ans += plus;
			}
			if(i < n) dp[i + 1] += dp_old[i] * (n - i) * rev;
		}
	}
	cout << ans + n;
	return 0;
}