#include<fstream>
using namespace std;
int n,i,j,k;
int cmmdc(int a, int b)
{
	while(a!=b)
	{
		if(a>b)a-=b;
		else b-=a;
	}
	return a;
}
int main()
{
	ifstream f("fractii.in");
	ofstream g("fractii.out");
	f>>n;
	k=2*n-1;
	for(i=2;i<=n;i++){
		
		for(j=2;j<=n;j++)
			if(cmmdc(i,j)==1&&i!=j)k++;
	}
//	for(i=2;i<=n;i++)
		
	g<<k;
	
}