from collections import deque

class CHT:
    def __init__(self):
        self.deq = deque()
        
    def check(self, f1, f2, f3):
        return (f2[0] - f1[0]) * (f3[1] - f2[1]) >= (f2[1] - f1[1]) * (f3[0] - f2[0])
    
    def f(self, f1, x):
        return f1[0]*x + f1[1]
    
    # add f_i(x) = a*x + b
    def add_line(self, a, b):
        f1 = (a, b)
        while len(self.deq) >= 2 and self.check(self.deq[-2], self.deq[-1], f1):
            self.deq.pop()
        self.deq.append(f1)
    
    # min f_i(x)
    def get(self, x):
        while len(self.deq) >= 2 and self.f(self.deq[0], x) >= self.f(self.deq[1], x):
            self.deq.popleft()
        return self.f(self.deq[0], x)
        
def solve(c, n):    
    n += 1
    H = [i for i in range(n)]
    dp = [0] * n
    cht = CHT()
    cht.add_line(-2 * H[0], H[0] ** 2)
    for i, h in enumerate(H[1:], 1):
        dp[i] = h ** 2 + c + cht.get(h)
        cht.add_line(-2 * h, dp[i] + h ** 2)
    return dp[-1]

for _ in range(int(input())):
    print(solve(*map(int, input().split())))