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

const int maxn = 1e6 + 10;
typedef long long ll;

ll sum[maxn];

void init() {
    for (int i = 1; i < maxn; i++) {
        sum[i] += sum[i-1] + i;
    }
}

int main() {
    int t;
    cin >> t;
    
    init();
    
    while (t--) {
        int n, m;
        cin >> n >> m;
        if (m >= n/2) {
            cout << 1LL*n*(n-1)/2 << endl;
        } else {
            cout << sum[n-1] - sum[n-1-m*2] << endl;
        }
    }
}