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