#include <iostream>
#include <fstream>
 
using namespace std;
 
int main()
{
    int n,x,y,s=0;
 
    ifstream f("fractii.in");
    ofstream g("fractii.out");
 
    f>>n;
 
    if(n>1)
    {
        for(x=2;x<=n;x++)
        {
            for(y=x+1;y<=n;y++)
            {
					while(x!=0 || y!=0)
					{
						if(x>y)
							x=x-y;
						else
							y=y-x;
					}
					if(x+y==1)
                    s++;
            }
 
            }
 
        g<<s*2+2*(n-1)+1;
    }
    else
        g<<0;
    return 0;
 
}