#include<fstream>
#define N 100000
#include<iostream>
using namespace std;
ifstream fin("fractii.in");
ofstream fout("fractii.out");
int v[N];
int main()
{
	int n;
	int i,j,m,s=0;
	double k;
	fin>>n;
	for(i=1;i<n;i++)
		for(j=i+1;j<=n;j++)
		{
			k=(double)i/j * 100000;
			m=(int)k;
			if(v[m]==0)
			{
				v[m]=1;
				s++;
			}
		}

	fout<<s*2+1<<endl;
	return 0;
}