#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
#define int ll
#define _FastIO ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0)
#define pb emplace_back
#define pii pair<int , int>
#define F first
#define S second
const int mod = 1000000007;
const int MAXX = 1e6 + 5;

int n;
int a[MAXX];

signed main()
{
    _FastIO;
    cin >> n;
    int x = 0 , y = 0 , z = 0;
    for(int i = 0; i < n; i++){
        cin >> a[i];
        if(a[i] == 1)
            x++;
        if(a[i] == 2)
            y++;
        if(a[i] > 2)
            z++;
    }
    int ans = (x * y) * 3;
    z += y;
    ans += ((z * (z - 1)) / 2);
    ans += ((x * (x - 1)));
    cout << ans << endl;
    return 0;
}