#include <bits/stdc++.h>
using namespace std;
const long long MOD = 998244353;
long long inv[5050 + 10], fac[5050 + 10], ifac[5050 + 10];
void setComb() {
  inv[0] = 1;
  inv[1] = 1;
  fac[1] = 1;
  ifac[1] = 1;
  fac[0] = 1;
  ifac[0] = 1;
  for (int i = 2; i < 5050; i++) {
    inv[i] = (-MOD / i) * inv[MOD % i] % MOD;
    fac[i] = fac[i - 1] * i % MOD;
    ifac[i] = ifac[i - 1] * inv[i] % MOD;
    inv[i] = (inv[i] + MOD) % MOD;
    fac[i] = (fac[i] + MOD) % MOD;
    ifac[i] = (ifac[i] + MOD) % MOD;
  }
  return;
}
long long comb(long long n, long long k) {
  if (n < k || n < 0 || k < 0)
    return 0;
  else
    return ((fac[n] * ifac[k] % MOD * ifac[n - k] % MOD + MOD) % MOD);
}
long long hcomb(long long n, long long r) {
  if (n == 0 && r == 0)
    return 1;
  else if (n < 0 || r < 0)
    return 0;
  else
    return comb(n + r - 1, r - 1);
}
int N;
vector<int> A;
long long dp[5050][5050];
long long cnt[5050];
void add(long long &a, long long b) { a = (a + b) % MOD; }
void mul(long long &a, long long b) { a = a * b % MOD; }
int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  cin >> N;
  A.resize(N);
  for (int i = 0; i < (N); ++i) cin >> A[i];
  sort(A.begin(), A.end());
  for (int i = 0; i < (N); ++i) cnt[A[i]]++;
  setComb();
  dp[0][0] = 1;
  for (int i = 0; i < N; i++) {
    long long sum = 0;
    for (int j = 0; j <= 5000; j++) {
      long long res = sum;
      mul(res, cnt[j]);
      mul(res, inv[N - i]);
      add(dp[i + 1][j], res);
      sum += dp[i][j];
    }
  }
  long long ans = 0;
  for (int i = 1; i < N; i++) {
    for (int j = 0; j <= 5000; j++) {
      long long res = dp[i][j];
      mul(res, cnt[j] - 1);
      mul(res, inv[N - i]);
      add(ans, res);
    }
  }
  cout << ans << endl;
  return 0;
}
