#include <iostream>
#include <stdlib.h>
#include <fstream>

using namespace std;
int main();
int _tmain(int, char*)
{
	return main();
}

int		g_pairs(0);
int		g_n;
int *	g_m;

int main()
{
	ifstream in("pairs.in");
	ofstream out("pairs.out");

	int i,j,a,b,aux;

	//	No.
	in >> g_n;

	//	Alloc vector
	g_m = (int*)malloc(g_n * sizeof(int));
	if( !g_m ) throw;

	//	Read vector
	int * number1 = g_m,*number2;
	for(i=0 ; i < g_n ; i++,number1++)
		in >> *number1;

	//	go..
	for(i=0,number1 = g_m ; i < g_n-1 ; i++,number1++)
	{
		for(j=i+1,number2 = number1+1; j < g_n; j++,number2++)
		{
			//	check prime
			a = *number1;
			b = *number2;

			while( b!=0 )
			{
				aux = b;
				b = a % b;
				a = aux;
			}

			if( a < 0 ) a = -a;
			if( a > 1 ) g_pairs++;
		}
	}

	out << g_pairs;
	in.close();
	out.close();
	free(g_m);
	return 0;
}