#include<iostream.h>
#include<fstream.h>
ifstream fin("fractii.in");
ofstream fout("fractii.out");
unsigned long n,p,q,r;
int ok=1;
int divizor(unsigned long x, unsigned long y)
{
	while(y!=0 && x!=y)
		{
		r=x%y;
		x=y;
		y=r;
		}
	if(x==1) return 1;
	else return 0;
}
int main()
{
fin>>n;
for(p=1;p<n+1;p++)
	for(q=p+1;q<n+1;q++)
		if(divizor(p,q)==1)
			ok+=2;
fout<<ok;
return 0;
}