#include<fstream>   
using namespace std;   
const int N=1000000;
int main()   
{   
    ifstream in("fractii.in");   
    ofstream out("fractii.out");   
    char c[N]={0};
	int a[100],n,i,j,x,l=1,ok,nr=0;   
   	in>>n;
	for (i=2;i*i<=n;i++)
		if (c[i]==0)
		{a[l]=i;
		l++;
		for (j=i+i;j<=n;j=j+i)
		c[j]=1;}
	for (i=1;i<=n;i++)
	for (j=1;j<i;j++)
	{ok=0;
	for (x=1;x<=n;x++)
		if (i%c[x]==0 && j%c[x]==0) ok++;
	if (ok==0) nr++;}
	out<<nr*2+1;
	in.close();   
	out.close();   
    return 0;   
}