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

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

long int	g_pairs(0);
long int	g_n;
long int	g_m[100000];

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

	int i,j,a,b,aux;
	int lda,ldb;

	//	Read 
	in >> g_n;
	for(i=0 ; i < g_n ; i++)
		in >> g_m[i];

	for(i=0; i < g_n-1 ; i++)
	{
		for(j=i+1; j < g_n; j++)
		{
			a = g_m[i];
			b = g_m[j];

			lda = a%10;
			ldb = b%10;

			if( (lda == 0 || lda == 2 ||
				 lda == 4 || lda == 6 || lda == 8 ) &&
				(ldb == 0 || ldb == 2 ||
				 ldb == 4 || ldb == 6 || ldb == 8 ) )
				 continue;

			 if( (lda == 0 || lda == 5) &&
				 (ldb == 0 || ldb == 5) )
				 continue;

			 if( (lda == 3 || lda == 6 || lda == 9 ) &&
				 (ldb == 3 || ldb == 6 || ldb == 9 ) )
				 continue;

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

			if(a == 1) g_pairs++;
		}
	}

	out << g_pairs;
	return 0;
}