#include <fstream>
using  namespace std;
ifstream in("fractii.in");
ofstream out("fractii.out");
int prime (long &i, long &j) {
	unsigned int r=i%j;
	while(r!=0) { 
		i=j; 
		i=r; 
		r=i%j; 
	}
	if(i==1) return 1;
	else return 0;
}
int main() {
	long N, i,j, nr;
	in>>N;
	nr=N;
	for(i=2;i<=N;i++) for(j=1; j<=N; j++) if(prime(i,j)) nr++;
	out<<nr;
	return 0;
}