#include<algorithm>
#include<iostream>
#include<cstring>
#include<cstdio>
#include<vector>
#include<queue>
#include<set>
#include<map>
using namespace std;
typedef long long ll;
const int maxn = 2000 + 100;
const int mod = 1e9 + 7;
const double EPS = 1e-10;
#define f(x) (x+x)
typedef long long ll;
const int INF = 0x3f3f3f3f;
int dcmp(double x, double y){
    if(fabs(x-y) < EPS) return 0;
    return x > y ? 1 : -1;
}
int main(){
    int t;
    scanf("%d", &t);
    while(t--){
        int n, m;
        scanf("%d%d", &n, &m);
        if(m >= n/2) printf("%lld\n",(long long)n*(n-1)/2);
        else{
            long long sum = (long long)n*(n-1)/2;
            long long sum1 = (long long)(n-m*2-1)*(n-2*m)/2;
            printf("%lld\n", sum-sum1);

        }

    }
    return 0;
}