#include<stdio.h>
int cmmdc(int a,int b)
{int r, cmmd;
do{
      if(a>b)
   	{
      r=a%b;
      a=b;
      b=r;
      cmmd=a;
      }
   else
      {
      r=b%a;
      b=a;
      a=r;
      cmmd=b;
      }
   }while (a>0&&b>0&&r>0);
   return cmmd;}
   int main()
{	int p,q,n,i,s;
   FILE*f,*g;
	i=0; s=1;
   f=fopen("fractii.in","r");
   fscanf(f,"%d",&n);
   fclose(f);
	for(q=2;q<=n;q++)
   	for(p=2;p<=q;p++)
       if(cmmdc(q,p)==1)
      {i=i+2;
         }
     s=1+2*(n-1);
     i=i+s;
   g=fopen("fractii.out","w");
   fprintf(g,"%d",i);
   fclose(g);
   return 0;
}