#include<iostream>
#include<algorithm>
#include<iomanip>
using namespace std;
long long n, m;
long long ans;
int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);

    int t;
    cin >> t;
    while (t--)
    {
        ans = 0;
        cin >> n >> m;
        if (n == 1 || m == 0)
        {
            cout << 0 << endl;
            continue;
        }

        if (n / 2 <= m)
        {
            ans = n * (n - 1) / 2;
        }
        else
        {
            ans = ((n - 1) + (n - 2 * m))*(2 * m) / 2;
        }
        cout << ans << endl;
    }
}