#include<bits/stdc++.h>
namespace {
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wunused-function"
#include<atcoder/all>
#pragma GCC diagnostic pop
using namespace std;
using namespace atcoder;
#define rep(i,n) for(int i = 0; i < (int)(n); i++)
#define rrep(i,n) for(int i = (int)(n) - 1; i >= 0; i--)
#define all(x) begin(x), end(x)
#define rall(x) rbegin(x), rend(x)
template<class T> bool chmax(T& a, const T& b) { if (a < b) { a = b; return true; } else return false; }
template<class T> bool chmin(T& a, const T& b) { if (b < a) { a = b; return true; } else return false; }
using ll = long long;
using P = pair<int,int>;
using VI = vector<int>;
using VVI = vector<VI>;
using VL = vector<ll>;
using VVL = vector<VL>;
using mint = modint998244353;

vector<mint> mul(const vector<mint>& f, const vector<mint>& g) {
  int fsz = f.size(), gsz = g.size();
  vector<mint> h(fsz + gsz - 1);
  rep(i, fsz) rep(j, gsz) h[i+j] += f[i] * g[j];
  return h;
}

vector<mint> section(vector<mint> f, int r) {
  int fsz = f.size();
  vector<mint> h;
  for(int i = r; i < fsz; i += 2) h.emplace_back(f[i]);
  return h;
}

} int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  int n, m;
  cin >> n >> m;
  vector<mint> p{1};
  while(m > 0) {
    p = section(mul(p, {1, n + 1, n}), m % 2);
    m /= 2;
  }
  mint ans = p[0];
  cout << ans.val() << '\n';
}