from math import gcd def jisuan_zuijian_zhenfenshu(n): a=list(map(int,input().split())) a=sorted(a) #排序 count=0 for i in range(len(a)-1): for j in range(i+1,len(a)): if gcd(a[i],a[j])==1: count+=1 return count n=int(input()) print(jisuan_zuijian_zhenfenshu(n))