def sieve(n):
    if n < 2:
        return []
    sieve = bytearray([True]) * (n + 1)
    sieve[0] = sieve[1] = False
    for i in range(2, int(n ** 0.5) + 1):
        if sieve[i]:
            sieve[i*i::i] = b'\x00' * len(sieve[i*i::i])
    primes = [i for i in range(2, n + 1) if sieve[i]]
    return primes

def main():
    import sys
    input = sys.stdin.read().split()
    N = int(input[0])
    L = int(input[1])
    denominator = N - 1
    if denominator == 0:
        print(0)
        return
    d_max = L // denominator
    if d_max < 2:
        print(0)
        return
    primes = sieve(d_max)
    k = len(primes)
    if k == 0:
        print(0)
        return
    sum_d = sum(primes)
    ans = (L + 1) * k - denominator * sum_d
    print(ans)

if __name__ == "__main__":
    main()