#include <bits/stdc++.h>
using namespace std;
using ll = long long;
const ll mod = 998244353;
ll dp[3030][3030][3];
int a[3030];
int main() {
  int n, k;
  cin >> n >> k;
  for (int i = 0; i < n; i++) cin >> a[i];
  dp[0][0][0] = 1;
  for (int i = 0; i < n; i++) {
    for (int j = 0; j <= k; j++) {
      dp[i + 1][j][0] = i + 1;
      (dp[i + 1][j][1] += dp[i][j][0] + dp[i][j][1]) %= mod;
      (dp[i + 1][j][2] += dp[i][j][0] + dp[i][j][1] + dp[i][j][2]) %= mod;
      if (j + a[i] <= k) {
        (dp[i + 1][j + a[i]][1] += dp[i][j][0] + dp[i][j][1]) %= mod;
        (dp[i + 1][j + a[i]][2] += dp[i][j][0] + dp[i][j][1]) %= mod;
      }
    }
  }
  cout << dp[n][k][2] << endl;
}
