#include<stdio.h>
int st[4], n, sol;

int cmmdc(int a, int b)
{
    if((!a) || (!b)) return a+b;
    if(a>b) return cmmdc(a%b,b);
    return cmmdc(a,b%a);
}

inline void back(int k)
{
	for(int i=1; i <= n; i++)
	{
		st[k] = i;
		if(k <= 2)
			if(k == 2 && cmmdc(st[1], st[2]) == 1)
				sol++;
			else
				back(k + 1);
	}
}

int main()
{
	FILE *f = fopen("fractii.in", "r");
	FILE *g = fopen("fractii.out", "w");

	fscanf(f, "%d", &n);

	back(1);
	
	fprintf(g, "%d", sol);

	fclose(f);
	fclose(g);

	return 0;
}