#include<bits/stdc++.h>
using namespace std;

typedef long long LL;
const int N = 1000010;
LL f[N], n;
LL m, T;

void init()
{
    f[1] = 1;
    for(LL i = 2; i < N; i ++)
        f[i] = f[i - 1] + i;
}

int main()
{
    init();
    cin >> T;
    while(T --)
    {
        cin >> n >> m;
        if(n == 1)
        {
            puts("0");
            continue;
        }

        if(m > (n / 2)) m = n / 2;

        cout << f[n - 1] - f[n - 2 * m - 1] << endl;
    }

    return 0;
}