#include <fstream>
#include <iostream>
using namespace std;
ifstream fin("fractii.in");
ofstream fout("fractii.out");
int main()
{
    int n,i,j,nr=0,a,b,ok,d;
    fin>>n;
    for(i=3;i<=n;i++)
    {
        ok=1;
        for(d=1;d*d<=i;d++)
            if(i%d==0)ok=0;
        if(ok==1)nr=nr+i-2;
        else
        for(j=2;j<=i-1;j++)
        {
                a=i;
                b=j;
                while(a!=b)
                    if(a>b)a-=b;
                    else b-=a;
                if(a==1)nr++;
        }
    }
    fout<<(nr+n)*2-1;
    return 0;
}