#include <iostream>
#include <fstream>
using namespace std;
int main(void)
{
	ifstream f("fractii.in");
	ofstream g("fractii.out");
	int n,k=0,i,j;
	f>>n;
	int p[n],q[n];
	for (i=1;i<=n;i++) p[i]=i;
	for (i=1;i<=n;i++) q[i]=i;
	for (i=1;i<=n;i++)
	{
		for (j=1;j<=n;j++)
		if (p[i]%q[j]!=0 || q[j]==1 || p[i]==1) k++;
	}
	g<<k;
	f.close();
	g.close();
	return 0;
}