#include <algorithm>
#include <cstdio>
#include <iostream>
#include <cmath>
#include <cstring>
using namespace std;
typedef long long ll;
const int N = 2000007;
ll f[N], n;
ll m, T;
void ini()
{
    for(int i=0;i<N;i++)
    {
        f[i]=0;
    }
}
void init()
{
    ini();
    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)
        {
            cout<<0<<endl;
            continue;
        }
        if(m > (n / 2)) m=n/2;
        cout << f[n - 1] - f[n - 2 * m - 1] << endl;
    }

    return 0;
}