#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define rep(i, s, n) for (int i = (s); i < (int)(n); i++)
#define rep2(i, n, s) for (int i = (n - 1); i >= (s); i--)

template<class T> inline bool chmin(T &a, T b) {
    if (a > b) {
        a = b;
        return true;
    }
    return false;
}
template<class T> inline bool chmax(T &a, T b) {
    if (a < b) {
        a = b;
        return true;
    }
    return false;
}

ll INF = 1000000000000000000;

// rep(i, 0, 4) => 上下左右, rep(i, 0, 8) => 斜めも含む
vector<int> dy = {-1, 0, 1, 0, -1, -1, 1, 1};
vector<int> dx = {0, 1, 0, -1, -1, 1, 1, -1};

int main() {
    int N;
    cin >> N;
    int X = 0, Y = 0, Z = 0;
    rep(i, 0, N) {
        int a;
        cin >> a;
        if (a == 1) X++;
        else if (a == 2) Y++;
        else Z++;
    }
    cout << X * (X - 1) + Y * (Y - 1) / 2 * Z * (Z - 1) / 2 + 3 * X * Y + Y * Z + 2 * X * Z << endl;
}