#include <stdio.h>

FILE *f,*g;
char p[100000][100000];
long i,j,n,contor;

int validare(long x,long y)
{
  long i;
  if(y % x == 0) return 0;
  for(i=2;i<=x;i++)
    if(p[x][i]!=0)
      if(p[x][i]==p[y][i])
	    return 0;
  return 1;
}

int main()
{
  f=fopen("fractii.in","r");
  g=fopen("fractii.out","w");
  fscanf(f,"%ld\n",&n);
  for(i=2;i<=n;i++)
    for(j=2;j<=i;j++)
	  if(i % j == 0)
	    p[i][j]=1;
  contor=2*n-1;
  for(i=2;i<n;i++)
    for(j=i+1;j<=n;j++)
	  contor+=2*validare(i,j);
  fprintf(g,"%ld\n",contor);
  fclose(f);   fclose(g);
  return 0;
}