#include <bits/stdc++.h>
using namespace std;
const int N = 5e3 + 1;
template <const int &MOD>
struct _m_int {
  int val;
  _m_int(int64_t v = 0) {
    if (v < 0) v = v % MOD + MOD;
    if (v >= MOD) v %= MOD;
    val = v;
  }
  static int mod_inv(int a, int m = MOD) {
    int g = m, r = a, x = 0, y = 1;
    while (r != 0) {
      int q = g / r;
      g %= r;
      swap(g, r);
      x -= q * y;
      swap(x, y);
    }
    return x < 0 ? x + m : x;
  }
  explicit operator int() const { return val; }
  explicit operator int64_t() const { return val; }
  _m_int &operator+=(const _m_int &other) {
    val -= MOD - other.val;
    if (val < 0) val += MOD;
    return *this;
  }
  _m_int &operator-=(const _m_int &other) {
    val -= other.val;
    if (val < 0) val += MOD;
    return *this;
  }
  static unsigned fast_mod(uint64_t x, unsigned m = MOD) {
    return x % m;
    unsigned x_high = x >> 32, x_low = (unsigned)x;
    unsigned quot, rem;
    asm("divl %4\n" : "=a"(quot), "=d"(rem) : "d"(x_high), "a"(x_low), "r"(m));
    return rem;
  }
  _m_int &operator*=(const _m_int &other) {
    val = fast_mod((uint64_t)val * other.val);
    return *this;
  }
  _m_int &operator/=(const _m_int &other) { return *this *= other.inv(); }
  friend _m_int operator+(const _m_int &a, const _m_int &b) {
    return _m_int(a) += b;
  }
  friend _m_int operator-(const _m_int &a, const _m_int &b) {
    return _m_int(a) -= b;
  }
  friend _m_int operator*(const _m_int &a, const _m_int &b) {
    return _m_int(a) *= b;
  }
  friend _m_int operator/(const _m_int &a, const _m_int &b) {
    return _m_int(a) /= b;
  }
  _m_int &operator++() {
    val = val == MOD - 1 ? 0 : val + 1;
    return *this;
  }
  _m_int &operator--() {
    val = val == 0 ? MOD - 1 : val - 1;
    return *this;
  }
  _m_int operator++(int) {
    _m_int before = *this;
    ++*this;
    return before;
  }
  _m_int operator--(int) {
    _m_int before = *this;
    --*this;
    return before;
  }
  _m_int operator-() const { return val == 0 ? 0 : MOD - val; }
  bool operator==(const _m_int &other) const { return val == other.val; }
  bool operator!=(const _m_int &other) const { return val != other.val; }
  bool operator<(const _m_int &other) const { return val < other.val; }
  bool operator<=(const _m_int &other) const { return val <= other.val; }
  bool operator>(const _m_int &other) const { return val > other.val; }
  bool operator>=(const _m_int &other) const { return val >= other.val; }
  _m_int inv() const { return mod_inv(val); }
  _m_int pow(int64_t p) const {
    if (p < 0) return inv().pow(-p);
    _m_int a = *this, result = 1;
    while (p > 0) {
      if (p & 1) {
        result *= a;
      }
      a *= a;
      p >>= 1;
    }
    return result;
  }
  friend ostream &operator<<(ostream &os, const _m_int &m) {
    return os << m.val;
  }
};
extern const int MOD = 998244353;
using mod_int = _m_int<MOD>;
mod_int fact[N], ifact[N], fq[N], dp[N][N], pref[N][N];
int n;
void pre() {
  fact[0] = 1;
  int i;
  for (i = 1; i < N; i++) {
    fact[i] = (fact[i - 1] * i);
  }
  ifact[N - 1] = fact[N - 1].inv();
  for (i = N - 2; i >= 0; i--) {
    ifact[i] = (ifact[i + 1] * (i + 1));
  }
}
mod_int ncr(int n, int r) {
  if (r > n) {
    return 0;
  }
  mod_int ans = (ifact[r] * ifact[n - r]);
  ans = (ans * fact[n]);
  return ans;
}
mod_int incr(int n, int r) {
  if (r > n) {
    return 0;
  }
  mod_int ans = (fact[r] * ifact[n - r]);
  ans = (ans * ifact[n]);
  return ans;
}
mod_int npr(int n, int r) {
  if (r > n) {
    return 0;
  }
  mod_int ans = ifact[n - r] * fact[n];
  return ans;
}
mod_int inpr(int n, int r) {
  if (r > n) {
    return 0;
  }
  mod_int ans = (fact[n - r] * ifact[n]);
  return ans;
}
signed main() {
  ios_base::sync_with_stdio(false), cin.tie(NULL), cout.tie(NULL);
  pre();
  int t = 1;
  while (t--) {
    cin >> n;
    dp[0][0] = 1;
    pref[0][0] = 1;
    for (int i = 1; i <= n; i++) {
      int x;
      cin >> x;
      fq[x]++;
      pref[0][i] = 1;
    }
    for (int len = 1; len <= n; len++) {
      pref[len][0] = 0;
      for (int x = 1; x <= n; x++) {
        dp[len][x] = (fq[x] * pref[len - 1][x - 1]);
        pref[len][x] = (dp[len][x] + pref[len][x - 1]);
      }
    }
    mod_int ans = 0;
    for (int last = 1; last <= n; last++) {
      if (fq[last] < 2) {
        continue;
      }
      for (int len = 0; len <= n - 2; len++) {
        mod_int add = (pref[len][last - 1] * npr((int)fq[last], 2));
        add = (add * inpr(n, len + 2));
        ans = (ans + add);
      }
    }
    cout << ans << endl;
  }
  return 0;
}
