#include <bits/stdc++.h>
#define be(v) (v).begin(),(v).end()
#define pb(q) push_back(q)
#define rep(i, n) for(int i=0;i<n;i++)
#define all(i, v) for(auto& i : v)
typedef long long ll;
using namespace std;
const ll mod=1000000007, INF=(1LL<<60);
#define doublecout(a) cout<<fixed<<setprecision(10)<<a<<endl;

int main() {
    cin.tie(0);
    cout.tie(0);
    ios::sync_with_stdio(false); 
    int n;
    cin >> n;
    map<int, ll> mp;
    vector<int> a(n);
    rep(i, n) {
        cin >> a[i];
        mp[a[i]]++;
    }
    ll ans = 0;
    vector<ll> v;
    for(auto [x, y] : mp) {
        v.pb(y);
    }
    ll num1 = 0, num2 = 0;
    all(e, v) {
        ans += num2 * e;
        num2 += num1 * e;
        num1 += e;
    }
    cout << ans << endl;


    return 0; 
}