#include<fstream>
using namespace std;
int n;
int cmmdc(int x,int i)
{
	if(x==i)
	return x;
	if(x>i) return cmmdc(x-i,i);
	if(x<i) return cmmdc(x,i-x);
}
int suma(int x)
{
	int i,s=0;
	for(i=2;i<=n;i++)
		if(x%i!=0&&i%x!=0&&cmmdc(x,i)==1)
			s++;
	return s;
}
int main()
{
	int i,s;
	ifstream f("fractii.in");
	ofstream g("fractii.out");
	f>>n;
	f.close();
	s=2*n-1;
	for(i=2;i<=n/2;i++)
		s=s+2*suma(i); 
	if(n%2==0&&(n/2)%2!=0)
		s=s+suma(n/2+1);
	if(n%2!=0)
		s=s+2*suma(n/2+1);
	g<<s;
	g.close();
	return 0;
}