#include<stdio.h>

long ggt(long a,long b){
 long aux;
 if(a<b){
  aux=a;
  a=b;
  b=aux;
 }
 while(b){
  aux=a%b;
  a=b;
  b=aux;
 }
return a;
}

long prim(long n){
 if(n%2==0&&n!=2)
  return 0;
 long i;
 for(i=3;i<n/2;i+=2)
  if(n%i==0)
   return 0;
 return 1;
}

int main(){
freopen("fractii.in","rt",stdin);
freopen("fractii.out","w+",stdout);

long n,ct=0;
scanf("%ld",&n);
long i,j;

for(i=1;i<=n;i++)
 if(prim(i)){
  for(j=1;j<=n;j++)
   if(j%i!=0||i==1)
    ct++;
 }
 else
  for(j=1;j<=n;j++)
   if(ggt(i,j)==1)
     ct++;
printf("%ld",ct);
}