#include<stdio.h>


int main()
{
 int r,n,i,j,nr=0,y,i1;
 
 FILE *f=fopen("fractii.in","r");
 FILE *g=fopen("fractii.out","w");

 fscanf(f,"%d",&n);
 for(i=2;i<n;i++)
	 for(j=i+1;j<=n;j++)
	 {
		
		if(j%i!=0)

			{if(j==(i+1))
			   nr++;
			 else
			  {r=j%i;
		       i1=i;
			   y=i1%r;
			   while(i1%r!=0)
				 {
			      y=i1%r;
				  i1=r;
				  r=y;
			    }
			   if(r==1)
				  nr++;
		     }
			    
			} 
	 }
 nr=nr*2+2*n-1;
 fprintf(g,"%d",nr);
}