#include<bits/stdc++.h> 
using namespace std;
int main()
{
    int t,i,j;
    long long ans,n,m;
    scanf("%d",&t);
    while(t--)
    {
        scanf("%lld%lld",&n,&m);
        ans=0;
        /*for(i=1;i<=m;++i)
        {
            if(n-2*i+1>0)ans+=n-2*i+1;
            else break;
            if(n-2*i>0)ans+=n-2*i;
            else break;
        }*/
        if(n-2*m>=0)ans=(n*2-2*m-1)*m;
        else
        {
            ans=(n-1)*n/2;
        }
        printf("%lld\n",ans);
    }
}