#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
template<class T> void check_min(T &a, const T &b){ a = (a < b) ? a : b; }
template<class T> void check_max(T &a, const T &b){ a = (a > b) ? a : b; }
#define all(x) (x).begin(), (x).end()

const ll N = 1e6 + 3;

ll n, a[N];
bool b[N];

int main(){
    ios::sync_with_stdio(false);
    cin.tie(NULL);

    cin >> n;
    for(ll i = 1; i <= n; ++i){
        cin >> a[i];
        b[a[i]] = true;
    }

    ll ans = 0;
    for(ll i = 1; i <= n; ++i){
        ll nxt = a[i] + 1;
        for(; nxt * nxt - a[i] * a[i] < N ; ++nxt)
            ans += b[nxt * nxt - a[i] * a[i]];
    }
    cout << ans << "\n";
}