#include using namespace std; #include using namespace atcoder; template inline bool chmax(T &a, T b) { return ((a < b) ? (a = b, true) : (false)); } template inline bool chmin(T &a, T b) { return ((a > b) ? (a = b, true) : (false)); } #define rep(i, n) for (long long i = 0; i < (long long)(n); i++) #define rep2(i, m ,n) for (int i = (m); i < (long long)(n); i++) #define REP(i, n) for (long long i = 1; i < (long long)(n); i++) typedef long long ll; #define updiv(N,X) (N + X - 1) / X #define l(n) n.begin(),n.end() #define YesNo(Q) Q==1?cout<<"Yes":cout<<"No" using P = pair; using mint = modint998244353; const int MOD = 998244353LL; const ll INF = 999999999999LL; vector fact, fact_inv, inv; /* init_nCk :二項係数のための前処理 計算量:O(n) */ template void input(vector &v){ rep(i,v.size()){cin>>v[i];} return; } void init_nCk(int SIZE) { fact.resize(SIZE + 5); fact_inv.resize(SIZE + 5); inv.resize(SIZE + 5); fact[0] = fact[1] = 1; fact_inv[0] = fact_inv[1] = 1; inv[1] = 1; for (int i = 2; i < SIZE + 5; i++) { fact[i] = fact[i - 1] * i % MOD; inv[i] = MOD - inv[MOD % i] * (MOD / i) % MOD; fact_inv[i] = fact_inv[i - 1] * inv[i] % MOD; } } /* nCk :MODでの二項係数を求める(前処理 int_nCk が必要) 計算量:O(1) */ long long nCk(int n, int k) { assert(!(n < k)); assert(!(n < 0 || k < 0)); return fact[n] * (fact_inv[k] * fact_inv[n - k] % MOD) % MOD; } long long modpow(long long a, long long n, long long mod) { long long res = 1; while (n > 0) { if (n & 1) res = res * a % mod; a = a * a % mod; n >>= 1; } return res; } ll POW(ll a,ll n){ long long res = 1; while (n > 0) { if (n & 1) res = res * a; a = a * a; n >>= 1; } return res; } int main() { ll n,q;cin>>n>>q; mint ans = 0; mint mul = 1; rep(i,n-1){mul *= (i+1);} rep(i,n){ mint ret = i+1; ret *= n;ret *= n+1;ret *= n+2; ret *= mul;ret /= (i+2);ret /= (i+3); ans += ret; } ans *= q; ans *= modpow((n*(n+1)/2)%998244353LL,q-1,(ll)(MOD)); cout<