def make_prime_table(n):
    sieve = list(range(max(n + 1, 2)))
    sieve[0] = -1
    sieve[1] = -1
    for i in range(4, n + 1, 2):
        sieve[i] = 2
    for i in range(3, int(n ** 0.5) + 1, 2):
        if sieve[i] != i:
            continue
        for j in range(i * i, n + 1, i * 2):
            if sieve[j] == j:
                sieve[j] = i
    return sieve


def enumerate_primes(n):
    t = make_prime_table(n)
    result = []
    if len(t) >= 3:
        result.append(2)
    for i in range(3, len(t), 2):
        if t[i] == i:
            result.append(i)
    return result


N, L = map(int, input().split())

t = L // (N - 1)
result = 0
for i in enumerate_primes(t):
    result += L - i * (N - 1) + 1
print(result)