from functools import reduce
from itertools import combinations
n, L, H = map(int, input().split())
A = list(map(int, input().split()))


def gcd(a, b):
    if b == 0:
        return a
    return gcd(b, a % b)


def lcm(a, b):
    return a*(b//gcd(a, b))


ans = 0
for k in range(1, n+1):
    for subset in combinations(A, k):
        x = reduce(lcm, subset)
        ans += H//x*(-1)**(k-1)*k
        ans -= (L-1)//x*(-1)**(k-1)*k

print(ans)