#include <fstream>
using namespace std;

ifstream homie("fractii.in");
ofstream doth("fractii.out");

int cmmdc( int a, int b )
{
    if( a == 0 )
        return b;
    while( a != b )
        if( a > b )
            a -= b;
        else
            b -= a;
    return b;
}

int main()
{
    int N, nrf = 0;
    homie >> N;
    for( int p = 1; p <= N; ++p )
        for( int q = 2; q <= N; ++q )
        {
            if( p == 1 && q == 1 )
            {
                ++nrf;
                continue;
            }
            if( cmmdc( p, q ) == 1 )
                ++nrf;
        }

    doth << nrf  << '\n';

    homie.close();
    doth.close();
    return 0;
}