#include <stdio.h>

bool prime(long a,long b)
{
	if(a%b==0)
	  return false;
	  return true;
}

int main()
{
	long N,K=0;
    FILE *fp;
    fp=fopen("fractii.in","r");
    fclose(fp);
    fp=fopen("fractii.out","w");
    fscanf(fp,"%l",&N);
    for(long i=1 ; i<=N ; i++)
      {
      	for(long j=1;j<=N;j++)
      	   if(prime(i,j)==true)
      	     K++;
      }
    fprintf(fp,"%l",K);
    fclose(fp);
}