#include<stdio.h>

FILE *f,*g;



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

	int i,n,a,b,j,ct;
	fscanf(f,"%d",&n);

	ct=4*n-5;
	for(i=2;i<n;i++)
		if(i%2==0)
		{for(j=i+3;j<=n;j=j+2)
			if(i%j!=0&&j%i!=0)
			       {a=i;b=j;
				while (a!=b)
					if (a>b)
						a-=b;
					else
						b-=a;
				if(a==1)
					ct=ct+2;
				}
		}
		else
		{
		for(j=i+2;j<=n;j++)
			if(i%j!=0&&j%i!=0)
			       {a=i;b=j;
				while (a!=b)
					if (a>b)
						a-=b;
					else
						b-=a;
				if(a==1)
					ct=ct+2;
				}
		}
	fprintf(g,"%d",ct);
	fprintf(g,"\n");
	fcloseall();
	return 0;
}