#include<stdio.h>
inline bool prime_intre_ele(int a,int b)
{
	if (a%2==0 && b%2==0)
		return 0;
	if (a%2!=b%2)
		return 1;
	if (a%b==0 || b%a==0)
		return 0;
	int r;
	while(b)
	{
		r=a%b;
		a=b;
		b=r;
	}
	if (a==1)
		return 1;
	return 0;
}
int main()
{
	freopen("fractii.in","r",stdin);
	freopen("fractii.out","w",stdout);
	int n,num,i,j;
	scanf("%d",&n);
	num=n*2-1;
	for(i=2;i<=n;++i)
		for(j=2;j<=n;++j)
			if (prime_intre_ele(i,j)==1)
				++num;
	printf("%d\n",num);
	return 0;
}