#include <cstdio>

long n, sol;

void Read()
{
    FILE *in = fopen( "fractii.in", "r" );

    fscanf( in, "%ld", &n );

    fclose( in );
}

long cmmdc( long a, long b )
{
    long c;

    while ( b )
    {
        c = a % b;
        a = b;
        b = c;
    }

    return a;
}

void Solve()
{
    int i = 0, j = 0;
    sol = n + (n - 1);

    for ( i = 2; i <= n; i++ )
        for ( j = 2; j <= n; j++ && i != j )
            if ( cmmdc( i, j ) == 1 )
                sol++;
}

void Write()
{
    FILE *out = fopen( "fractii.out", "w" );

    fprintf( out, "%ld", sol );

    fclose( out );
}

int main( void )
{
    Read();
    Solve();
    Write();

    return 0;
}