#include <bits/stdc++.h>
#include <atcoder/modint>

using namespace std;
using namespace atcoder;

using mint = modint998244353;

int main()
{
    int n, k;
    cin >> n >> k;
    vector<int> a(n);
    for (auto &&x : a)
    {
        cin >> x;
    }
    sort(a.begin(), a.end());
    auto acopy = a;
    acopy.erase(unique(acopy.begin(), acopy.end()), acopy.end());
    for (auto &&x : a)
    {
        x = lower_bound(acopy.begin(), acopy.end(), x) - acopy.begin();
    }
    vector<int> acount(n);
    for (auto &&x : a)
    {
        acount.at(x)++;
    }
    vector dp(n + 1, vector<mint>(k + 1));
    dp.at(0).at(0) = 1;
    for (int i = 0; i < n; i++)
    {
        for (int j = 0; j <= k; j++)
        {
            for (int jnew = j; jnew <= min(k, j + i); jnew++)
            {
                dp.at(i + 1).at(jnew) += dp.at(i).at(j);
            }
        }
    }
    auto ans = dp.at(n);
    for (int i = 0; i < n; i++)
    {
        int64_t d = acount.at(i);
        if (d <= 1)
        {
            continue;
        }
        for (int j = 0; j <= k; j++)
        {
            mint x = ans.at(j);
            for (int jnew = j + 1; jnew <= min(int64_t(k), j + d * (d - 1) / 2); jnew++)
            {
                ans.at(jnew) -= x * dp.at(d).at(jnew - j);
            }
        }
    }
    cout << ans.at(k).val() << endl;
    return 0;
}