def calc(x, m):
    T = []
    st = max(1, x // m)
    pre = x + 1
    for i in range(st, x + 1):
        now = x // i
        if pre == now:
            break
        T.append(x // i)
        pre = now
    T += list(reversed(range(now)))
    nt = len(T)
    ret = x * m
    for i in range(nt - 1):
        a, b = T[i], T[i + 1]
        ret -= (a - b) * (a + b + 1) // 2 * (x // a)
        #print(i, a, b, x // a, (a - b) * (a + b + 1) // 2 * (x // a))
    return ret

N, M = map(int, input().split())
ans = 0
for i in range(1, N + 1):
    ans = max(ans, calc(i, M))
print(ans)