#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define ALL(v) v.begin(),v.end()
typedef long long ll;
 
#include<bits/stdc++.h>
using namespace std;

int main(){
  int n;
  cin>>n;
  vector<ll> A(n);
  rep(i,n) cin>>A[i];
  
  ll cnt1=0,cnt2=0,cnt3=0;
  rep(i,n){
    if(A[i]==1) cnt1++;
    else if(A[i]==2) cnt2++;
    else cnt3++;
  }
  
  ll ans=(cnt2+cnt3)*(cnt2+cnt3-1)/2+2*cnt1*(cnt1-1)/2+2*cnt1*cnt3+3*cnt1*cnt2;
  cout<<ans<<endl;

  return 0;
}