#include <bits/stdc++.h>

using namespace std;

int t,n,r;

int verif (long long val){
    long long nr = sqrt(val);
    if (sqrt(val) == nr)
        return 1;

    nr++;
    if (nr*(nr-1)+1 <= val && val <= nr*nr)
        return 1;
    return 0;
}
int main (){

    ifstream cin ("progresie.in");
    ofstream cout ("progresie.out");

    cin>>t;
    for (;t--;){
        cin>>n>>r;
        for (long long i=1;;i++){
            long long val = i * (i-1)+1;
            int ok = 1;
            for (int j=1;j<=n;j++){
                if (!verif(val)){
                    ok = 0;
                    break;
                }
                val += r;
            }

            if (ok){
                cout<<i*(i-1)+1<<"\n";
                break;
            }
        }
    }

    return 0;
}