#include <stdio.h>
#define infile "fractii.in"
#define outfile "fractii.out"


int n, i, j;
int rez;


int cmmdc(int,int);


int main()
{
	freopen(infile, "r", stdin);
	scanf("%d", &n);
	fclose(stdin);
	rez=n;
	for (i=2; i<=n; i++)
	{
		rez++;
		for (j=2; j<=n; j++)
			if (cmmdc(i,j)==1)
				rez++;
	}
	freopen(outfile,"w", stdout);
	printf("%d", rez);
	fclose(stdout);
	return 0;
}


int cmmdc(int x,int y)
{
	int r;
	while (y)
	{
		r=x%y;
		x=y;
		y=r;
	}
	return x;
}