N, L = list(map(int, input().strip().split(' ')))
ans = 0
NMAX = 10 ** 7
nonprime = [False] * (NMAX + 1)
for i in range(3, len(nonprime), 2):
    if nonprime[i]:
        continue
    if i * (N - 1) > L:
        break
    ans += L - i * (N - 1) + 1
    j = 3
    while i * j <= NMAX:
        nonprime[i * j] = True
        j += 2
if 2 * (N - 1) <= L:
    ans += L - 2 * (N - 1) + 1
print(ans)