using System;
using static System.Console;
using System.Linq;
using System.Collections.Generic;

class Program
{
    static int NN => int.Parse(ReadLine());
    static int[] NList => ReadLine().Split().Select(int.Parse).ToArray();
    static int[][] NArr(long n) => Enumerable.Repeat(0, (int)n).Select(_ => NList).ToArray();
    public static void Main()
    {
        Solve();
    }
    static void Solve()
    {
        var n = NN;
        var a = NList;
        var count = new long[4];
        var ans = 0L;
        foreach (var ai in a)
        {
            if (ai == 1) ans += count[1] * 2 + count[2] * 3 + count[3] * 2;
            else if (ai == 2) ans += count[1] * 3 + count[2] + count[3];
            else ans += count[1] * 2 + count[2] + count[3];
            if (ai < 3) ++count[ai];
            else ++count[3];
        }
        WriteLine(ans);
    }
}