#include <bits/stdc++.h>
using namespace std;
typedef long long int ll ;
int main() {
ll n;
cin>>n ;
vector <ll> b(n+5,0);
ll i = 0 ;
while(i<=n-1){
cin>>b[i];
i++;
}
ll gg = 0 ;
i = 0 ;
while(i<=n-1){
ll j = i + 1 ;
while(j<=n-1){
if(b[i]+b[j]>=(b[i]*b[j])){
gg++;
}
j++;
}
i++;
}
cout<<gg ;
return 0 ;
}