//Δ_1003
#include<iostream>
#include<cstdio>
#include<fstream>
#include<algorithm>
#include<vector>
#include<map>
#include<set>
#include<queue>
#include<bitset>
#include<cmath>
#include<cstring>
#include<cstdlib>
using namespace std;
typedef long long LL;
typedef double DB;
LL c(int x){
    if(x<0)
        return 0;
    return (LL)x*(x-1)/2;
}
int main()
{
    int T,n,m;
    scanf("%d",&T);
    while(T--){
        scanf("%d%d",&n,&m);
        cout<<c(n)-c(n-m*2)<<endl;
    }
    return 0;
}