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

using ll = long long;
#define fi first
#define se second

int main(){
  int n;
  cin>>n;
  ll a[n];
  ll count[4]={};
  for(int i=0;i<n;i++){
    cin>>a[i];
    if(a[i]<1||a[i]>1e9){
      cout<<i<<" : "<<"WARNING"<<endl;
    }
    if(a[i]>3){
      a[i]=3;
    }
    count[a[i]]++;
  }
  ll x=count[1],y=count[2],z=count[3];
  ll ans=(y*(y-1))/2+y*z+(z*(z-1))/2+x*(x-1)+2*x*z+3*x*y;
  cout<<ans<<endl;
}