from math import sqrt

def solve():
    n, l = map(int, input().split())
    ans = 0
    primes = ()
    for i in range(2, int(sqrt(l)) + 1):
        for j in primes:
            if i % j == 0:
                break
        else:
            primes = primes + (i,)

    for prime in primes:
        if (l + 1) < (n - 1) * prime:
            break
        ans += (l + 1) - (n - 1) * prime
    print(ans)

if __name__=="__main__":
    solve()