#include <stdio.h>

int main ()
{
	freopen("fractii.in", "r", stdin);
	freopen("fractii.out", "w", stdout);
	int n, c, i, j, x, y, z;
	scanf("%d", &n);
	c=2*n-1;
	for (i=2; i<=n; i++) {
		for (j=i-1; j>1; j--) {
			x=i;
			y=j;
			z=x%y;
			while (z!=0) {
				x=y;
				y=z;
				z=x%y;
			}
			if (y==1) {
				c=c+1;
			}
		}
		for (j=i+1; j<=n; j++) {
			x=j;
			y=i;
			z=x%y;
			while (z!=0) {
				x=y;
				y=z;
				z=x%y;
			}
			if (y==1) {
				c=c+1;
			}
		}
	}
	printf("%d", c);
	return 0;
}