#include<stdio.h>


long int n;
long int fr[10000];


void creare()
{
 int i;
 for(i=1; i<=n; i++)
  {
   fr[i]=n-1;
  }
 fr[1]=n;
}


void adunare()
{
 FILE *f=fopen("fractii.out", "w");
 long int s=0, i;
 for(i=1; i<=n; i++)
  {
   s=s+fr[i];
  }
 fprintf(f, "%ld", s);
 fclose(f);
}


int cmmdc(long int a, long int b)
{
 long int r;
 while(a%b!=0)
  {
   r=a%b;
   a=b;
   b=r;
  }
 return b;
}


void lista()
{
 long int t, j, i;
 for(i=1; i<=n; i++)
  {
   for(j=i+1; j<=n; j++)
    {
     t=cmmdc(i, j);
     if(t!=1)
      {
       fr[i]--;
       fr[j]--;
      }
    }
  }
}


int main()
{
 FILE *f=fopen("fractii.in", "r");
 fscanf(f, "%ld", &n);
 fclose(f);
 creare();
 fclose(f);
 lista();
 adunare();

 return 0;

}