import sys

def main():
    X, Y = map(int, sys.stdin.readline().split())
    if X == 0:
        X = 1
    max_R = Y
    sieve = list(range(max_R + 1))
    for i in range(2, int(max_R**0.5) + 1):
        if sieve[i] == i:
            for j in range(i * i, max_R + 1, i):
                if sieve[j] == j:
                    sieve[j] = i
    max_f = 0
    for R in range(X, Y + 1):
        if R == 1:
            current = 4
        else:
            temp = R
            res = 1
            valid = True
            while temp > 1:
                p = sieve[temp]
                cnt = 0
                while temp % p == 0:
                    cnt += 1
                    temp //= p
                mod_p = p % 4
                if mod_p == 3:
                    if cnt % 2 != 0:
                        valid = False
                        break
                elif mod_p == 1:
                    res *= (cnt + 1)
            if valid:
                current = res * 4
            else:
                current = 0
        if current > max_f:
            max_f = current
    print(max_f)

if __name__ == '__main__':
    main()