from math import sqrt
N, L = map(int, input().split())
result = 0
max_interval = int(L//(N-1))

primes = set(range(2, max_interval+1))
for i in range(2, int(sqrt(max_interval))+1):
    primes.difference_update(range(i*2, max_interval+1, i))

for x in primes:
    d = x*(N-1)
    result += L-d+1

print(result)