#ifdef ONLINE_JUDGE
#pragma GCC optimize("Ofast,no-stack-protector,unroll-loops,fast-math")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4.1,sse4.2,avx,avx2,popcnt")
#include <immintrin.h>
#include <emmintrin.h>
#endif
#include <bits/stdc++.h>

#define rep(i, a, b) for(int i = (a), i##end = (b); i <= i##end; i++)
#define _rep(i, a, b) for(int i = (a), i##end = (b); i >= i##end; i--)
#define ec first
#define fb second
#define dl make_pair
#define dk(...) make_tuple(__VA_ARGS__)
#define de(val) cerr << #val << " = " << (val) << endl

using namespace std;

typedef long long ll;
typedef __int128 i128;
typedef pair <int, int> pii;

int read() {
	int x = 0, f = 1; char c = getchar();
	while (!isdigit(c)) {
		if (c == '-') f = -1;
		c = getchar();
	}
	while (isdigit(c)) {
		x = (x << 3) + (x << 1) + (c ^ 48);
		c = getchar();
	}
	return x * f;
}

template <typename _Tp>
void print(_Tp x) {
	if (x < 0) putchar('-'), x = -x;
	static int sta[40];
	int top = 0;
	do sta[top++] = x % 10, x /= 10; while (x);
	while (top) putchar(sta[--top] + 48);
}

int T;

signed main() {
	T = read();
	while (T --> 0) {
		int a = read(), b = read();
		int ans1 = b * (b + 1) / 2;
		if (a > 2) ans1++;
		else ans1 += b + 1;
		int ans2 = b * (b - 1) / 2;
		if (a > 3) ans2++;
		else if (a != 3) ans2 = 1e9;
		else ans2 += 3;
		int ans = min(ans1, ans2);
		print(ans), puts("");
	}
	return 0;
}