#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
using ll = long long;
using ull = unsigned long long;
#define rep(i,n) for(int i=0; i<(n); i++)

const ull MOD = 998244353;

int N,K;
vector<int> A;
vector<int> C;
vector<vector<ull>> dp;

int main(){
  cin >> N >> K;
  A.resize(N);
  rep(i,N) cin >> A[i];
  sort(A.begin(),A.end());
  C.push_back(1);
  rep(i,N-1) if(A[i] == A[i+1]) C.back()++; else C.push_back(1);

  dp.push_back(vector<ull>(K+1,0));
  dp[0][0] = 1;
  for(int c=0; c<N; c++){
    vector<ull> buf(K+1,0);
    for(int i=0; i<=K; i++){
      buf[i] += dp.back()[i];
      if(i+c+1 <= K) buf[i+c+1] += MOD - dp.back()[i];
    }
    rep(i,K) buf[i+1] = (buf[i] + buf[i+1]) % MOD;
    dp.emplace_back(move(buf));
  }
  
  vector<ull> ans = dp.back();
  for(int c : C) if(c != 1){
    for(int k=0; k<=K; k++){
      for(int dk=1; dk<=c*(c-1)/2 && k+dk<=K; dk++){
        ans[k+dk] += (MOD - ans[k]) * dp[c][dk];
        ans[k+dk] %= MOD;
      }
    }
  }

  cout << ans[K] << "\n";
  return 0;
}