#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
int cmmdc(int a, int b)
{
	while (a != b)
	{
		if (a > b)
			a = a - b;
		else
			b = b - a;
	}
	return a;
}
int main()
{
	int n,i,j,s=0;
	FILE* p,*q;
	p = fopen("fractii.in", "r");
	q = fopen("fractii.out", "w");
	fscanf(p,"%d", &n);
	for (i = 2; i <= n; i++)
		for(j=2;j<=n;j++)
	{
			if (cmmdc(i, j) == 1)
				s++;
	}
	s = s + (2 * n - 1);
	fprintf(q, "%d", s);
	fclose(p);
	fclose(q);	
	return 0;
}