#include<stdio.h>

FILE *f=fopen("pairs.in","r"), *g=fopen("pairs.out","w");

long long n,m[10000],i,j,s;

int prim(int x,int y) {
   if(x==1 || y==1) return 1;
   if(x==y || y==0 || x==0) return 0;
   if(x>y) return prim(y,x%y);
   else return prim(x,y%x);
}

int main() {
   fscanf(f,"%lld",&n);
   for(i=0;i<n;i++) {
      fscanf(f,"%lld",&m[i]);
   }
   for(i=0;i<n-1;i++) {
      for(j=i+1;j<n;j++)
	 if(prim(m[i],m[j])) s++;
   }
   fprintf(g,"%lld",s);
   fcloseall();
   return 0;
}