#include<fstream>
#include<cmath>
using namespace std;
ifstream cin("progresie.in");
ofstream cout("progresie.out");
int main()
{
	int t;
	for(cin>>t;t--;) {
		int i=1,n,r;
		cin>>n>>r;
		for(bool o=1;o;) {
			int j=1;
			long long v=1LL*i*(i-1)+1;
			for(long long e=i-1;j<n;++j) {
				long long l=v+1LL*j*r,b=sqrt(l-1)+1,x=1LL*b*(b-1)+1;
				if(l<x?v+=x-l,e+=l-x:e=min(e,1LL*b*b-l),l+e<x)
					break;
			}
			j==n?cout<<v<<'\n',o=0:++i;
		}
	}
	return 0;
}