#include <iostream>
#include <fstream>
using namespace std;

int main()
{
    int n,c,i,j,k=1,x,y;
    ifstream f("fractii.in");
    ofstream g("fractii.out");
    f>>n;
    for(i=1;i<=n-1;i++)
        for(j=i+1;j<=n;j++)
            {
                x=i;
                y=j;

                while(x)
                    {
                        c=y%x;
                        y=x;
                        x=c;
                    }
                if(y==1) k=k+2;

            }
    g<<k;

    return 0;
}