from sortedcontainers import SortedList
limit = 100
distinct_prime_factor_count = [0]*(limit+1)
primes = []
for i in range(2, limit+1):
    if distinct_prime_factor_count[i] == 0:
        primes.append(i)
        for num in range(i, limit+1, i):
            distinct_prime_factor_count[num] += 1
primes_set = set(primes)

A, B = map(int, input().split())

def f(x):
    return x**3 - x**2 + x + 1

ans = 0
for i in range(A, B + 1):
    if i in primes_set:
        ans += f(i)
print(ans)