import sys
def main():
    input = sys.stdin.readline
    N,S = map(int, input().split())
    A = list(map(int, input().split()))
    MOD = 998244353

    dp = [[[0 for _ in range(3)] for _ in range(S+1)] for _ in range(N+1)]
    dp[0][0][0] = 1
    for i in range(N):
        a = A[i]
        for j in range(S+1):
            dp[i+1][j][0] = (dp[i+1][j][0] + dp[i][j][0]) % MOD
            dp[i+1][j][1] = (dp[i+1][j][1] + dp[i][j][1]) % MOD
            dp[i+1][j][2] = (dp[i+1][j][2] + dp[i][j][2]) % MOD

            if j+a > S: continue
            dp[i+1][j+a][1] = (dp[i+1][j+a][1] + dp[i][j][1] + (dp[i][j][0] * (i+1))) % MOD
            dp[i+1][j+a][2] = (dp[i+1][j+a][2] + (dp[i][j][1] * (N-i)) + (dp[i][j][0] * (i+1) * (N-i))) % MOD

    print(dp[N][S][2])

if __name__ == '__main__':
    main()