#include <fstream>

using namespace std;
ifstream fin("fractii.in");
ofstream fout("fractii.out");
int i,j,nr,n;
int cmmdc (int a,int b)
{
    while(a!=b)
    {
        if(a>b)
            a=a-b;
        else
            b=b-a;
    }
    return a;
}
int main()
{
    fin>>n;
    for(i=1;i<=n;i++)
       for(j=2;j<=n;j++)
            if(i<j && cmmdc(i,j)==1)
                nr++;
    for(i=n;i>=2;i--)
        for(j=1;j<=n-1;j++)
            if(i>j && cmmdc(i,j)==1)
                nr++;
fout<<nr+1;
    return 0;
}