N, L, H = [int(i) for i in input().split()]
C = [int(i) for i in input().split()]
ans_cnt=0
if N==1 and C[0]==1:
    print(H-L+1)
else:
    for j in range(L,H+1):
        sub_cnt=0
        for k in range(N):
            if j%C[k]==0:
                sub_cnt+=1
                if sub_cnt==2:
                    break
        if sub_cnt==1:
            ans_cnt+=1
    print(ans_cnt)