#include<fstream.h>
#define fin "fractii.in"
#define fout"fractii.out"
int main()
{	int n,p,q,r,k,a,b;
	ifstream in(fin);
	in>>n;
	k=0;
	for(p=2;p<n;p++)
		{ for(q=p+1;q<=n;q++) { a=p;
					b=q;
					r=a%b;
				      while(r!=0) {a=b;  b=r;  r=a%b;}
				      if(b==1) k++;
				    }
		}
	k=k+n-1;
	k=k*2+1;
	ofstream out(fout);
	out<<k<<"\n";
	out.close();
	return 0;
}