#!/usr/bin/ruby
N,X,Y,*A=`dd`.split.map &:to_i
B=[]
s=0
(1...1<<N).each{|i|
	d=0
	r=1
	N.times{|j|(r=r.lcm(A[j]);d+=1) if i[j]>0}
	q=Y/r-(X-1)/r
	if d==2
		B<<r
	end
	if d%2>0
		s+=q*d
	else
		s-=q*d
	end
}
p s