/*
 * Author: nskybytskyi
 * Time:   2022-01-07 14:20:00
 */

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

int main() {
  cin.tie(0)->sync_with_stdio(0);

  int t; cin >> t; while (t--) {
    int n, m;
    cin >> n >> m;

    if (m <= n) {
      cout << m / 2 << "\n";
    } else {
      cout << ((m - n) * 1ll * (m - n + 5)) / 2 + m + 1 << "\n";
    }
  }

  return 0;
}