#include<fstream>
using namespace std;
 
int cmmdc(long int a,long int b)
{
	long int r;
	while(b!=0)
	{
		r=a%b;
		a=b;
		b=r;
	}
	if(a==1)
		return 1;
	else
		return 0;
}
 
int main()
{
	ifstream fin("fractii.in");
	ofstream fout("fractii.out");
	long int i,j,n,s;
	s=0;
	fin>>n;
	for(i=1;i<=n;i++)
	{
		for(j=1;j<=i;j++)
		{
			if(cmmdc(i,j)==1)
				s=s+2;
		}
	}
	fout<<s;
	return 0;
}