#include<bits/stdc++.h>
using namespace std;
ifstream F("progresie.in");
ofstream G("progresie.out");
int t;
long long n,r,x,l,j,k,i;
bool s,o;
int main()
{
    for(F>>t;t;--t)
        for(F>>n>>r,x=(long long)(r*(n-1)+1),s=0,i=1;i<=x&&!s;++i) {
            for(j=(long long)(i*i-i+1),o=1,k=1;k<=n&&o;++k,j+=r)
                l=(long long)sqrt((long long)(j)),o=((long long)(j)==(long long)(l*l)||(long long)(j)>(long long)((l-1)*(l-2)));
            if(o)
                s=1,G<<(long long)(i*i-i+1)<<'\n';
        }
    return 0;
}