#include <bits/stdc++.h>

#define MaxN 100005
#define MOD 666013
#define INF 2140000000
using namespace std;

FILE*IN,*OUT;

int T,N,R;

int main()
{
    IN=fopen("progresie.in","r");
    OUT=fopen("progresie.out","w");

    fscanf(IN,"%d",&T);

    for(int t=1;t<=T;t++)
    {
        fscanf(IN,"%d%d",&N,&R);
        for(long long i=1;;i++)
        {
            long long start=i*(i-1)+1,left=i-1;
            bool p=1;
            for(int j=1;j<N;j++)
            {
                start+=R;
                long long r=sqrt(start-1)+1;
                long long lw=r*(r-1)+1,hi=r*r;
                if(start<lw)
                {
                    if(start+left<lw)
                    {
                        p=0;
                        break;
                    }
                    left-=lw-start;
                    start=lw;
                }
                left=min(left,hi-start);
            }
            if(p)
            {
                fprintf(OUT,"%lld\n",start-1LL*R*(N-1));
                break;
            }
        }
    }

    return 0;
}