#include<fstream.h>   
#include<math.h>   
int n,s;   
ifstream f("fractii.in");   
ofstream g("fractii.out");   
int prim(int a,int b)   
{while(a!=b)   
    if(a>b) a-=b;   
    else b-=a;   
 if(a==1) return 1;   
 else return 0;   
}    
int main()
{//int p;
 f>>n;
 s=2*n-1;
 for (int i=2;i<n;i++)
	for(int j=i+1;j<=n;j++)
		if (prim(i,j)) s+=2;
 g<<s;
 f.close();
 g.close();
 return 0;
}