#include<fstream>
using namespace std;
ifstream fin("fractii.in");
ofstream fout("fractii.out");
unsigned n,v[100],s=1;

void ireductibil()
{ for(unsigned i=1;i<=n;i++)
	{ for(unsigned j=1;j<=n;j++)
		if(v[i]%v[j]!=0&&v[j]%v[i]!=0)
			//fout<<v[i]<<"/"<<v[j]<<" ";
		    s++;
	}
}


int main()
{ fin>>n;
  for(unsigned i=1;i<=n;i++)
	  v[i]=i;

  //for(unsigned i=1;i<=n;i++)
	  //fout<<v[i]<<" ";
ireductibil();
  s+=(n-1)*2;
  fout<<s;
}