#include <fstream>

using namespace std;

ifstream fin ("fractii.in");
ofstream g ("fractii.out");

int prim(int x, int y)
{
    int r;
    while(y)
    {
        r=x%y;
        x=y;
        y=r;
    }
    return x;
}

int main()
{
    int cnt=0, n, p, q;
    fin >> n;
    cnt+=n*2-1;
    for(p=2; p<=n; p++)
        for(q=p+1; q<=n; q++)
            if(prim(p, q)==1)
                cnt+=2;
    g<< cnt;
    return 0;
}