def solve():
    n, m = map(int, input().split())
    if n >= m:
        print(m // 2)
    elif n + n - 1 < m:
        ans = n * (1 + n) // 2 + n - 2
        print(ans)
    elif m % 2 == 1:
        d = n - m // 2
        ans = d - 1
        n = m // 2 - d + 1
        ans += n * (1 + n) // 2 + n - 2
        print(ans)
    else:
        d = n - m // 2
        ans = d
        n = m // 2 - d
        ans += n * (1 + n) // 2 + n - 2
        print(ans)
    
for _ in range(int(input())):
    solve()