import math
from collections import deque

N, L, H = map(int, input().split())
C = list(map(int, input().split()))

def calc(n):
    ret = deque()
    cnt = 0
    while n > 0:
        if n & 1:
            ret.append(C[cnt])
        n >>= 1
        cnt += 1
    return ret

ans = 0
for i in range(1, 1 << N):
    d = calc(i)
    num = len(d)
    if num == 1:
        v = d.pop()
        ans += H // v - (L-1) // v
        continue

    while len(d) > 1:
        v1 = d.pop()
        v2 = d.pop()
        d.append(v1*v2//math.gcd(v1,v2))
    v = d.pop()
    if num % 2 == 1:
        ans += (H // v - (L-1) // v)*num
    else:
        ans -= (H // v - (L-1) // v)*num

print(ans)