from math import isqrt
def A004125(n): return n**2+((s:=isqrt(n))**2*(s+1)-sum((q:=n//k)*((k<<1)+q+1) for k in range(1, s+1))>>1)


import sys
input = sys.stdin.readline
N, M = map(int, input().split())
ans = 0
for i in range(1, N+1):
    tmp = i*(M-i)
    tmp += A004125(i)
    ans = max(ans, tmp)
print(ans)