#include <bits/stdc++.h>

using namespace std;

ifstream f("progresie.in");
ofstream g("progresie.out");

bool inSeq(uint64_t x)
{
    uint64_t sqx=sqrt(x);
    if(sqx*sqx!=x) sqx++;
    else return true;
    return sqx*(sqx-1)+1<=x && x<sqx*sqx;
}

int main()
{
    int T;
    f>>T;
    for(int N,R;T--;)
    {
        f>>N>>R;
        bool found=false;
        int k=1,x0;
        while(!found)
        {
            uint64_t x=(k-1)*k+1;
            x0=x;
            int cnt=1;
            while(cnt<N)
            {
                x+=R;
                if(!inSeq(x)) break;
                cnt++;
            }
            k++;
            found=(cnt==N);
        }
        g<<x0<<'\n';
    }

    return 0;
}