#include <iostream>
#include <fstream>

int main() {

	int n, i, j, k, nr;
	bool okay;
	std::ifstream in;
	std::ofstream out;

	in.open("fractii.in");
	if ( in.fail() ) return 1;
	in >> n;
	in.close();
	nr = 2 * n - 1;

	for ( i = 2; i <= n; i++ ) {
		for ( j = 2; j < i; j++ ) {
			if ( i % j == 0 || ( i % 2 == 0 && j % 2  == 0 ) ) continue;
			okay = 1;
			for ( k = 3; k <= j; k++ ) {
				if ( j % k == 0 && i % k == 0 ) {
					okay = 0;
					break;
				}
			}
			if ( okay ) nr += 2;
		}
	}

	out.open("fractii.out");
	if ( out.fail() ) return 1;
	out << nr << std::endl;
	out.close();

	return 0;
}