#include<fstream>
using namespace std;
long int x,y;
int cmmdc(long int x,long int y)
{
	if(x>y)
		return cmmdc(x%y,y);
	else if(y>x)
		return cmmdc(y%x,x);
	else
		return x;
}
int main()
{
	int n,cont=1;
	ifstream f("fractii.in");
	f>>n;
	for(x=1;x<n;x++)
		for(y=x+1;y<=n;y++)
			if(cmmdc(x,y)==1)
				cont+=2;
	ofstream g("fractii.out");
	g<<cont<<"\n";
	return 0;
}