#include<fstream.h>
ifstream fin("fractii.in");
ofstream fout("fractii.out");
long n,i,j,i1,j1,s,c,k,min;
int sw;
int main()
{fin>>n;s=2*n-1;
 for(i=2;i<=n;i++)
  for(j=2;j<=n;j++)
  { if(i==j)break; else {
    sw=1;
    if(i<=j)min=i;else min=j;
    for(k=2;k<=min;k++)
      if(i%k==0 && j%k==0){sw=0;break;}
    if(sw==1)s++;     }
  }
 fout<<s;
fin.close();
fout.close();
return 0;
}