#include <stdio.h>
unsigned long n;



unsigned long cmmdc(unsigned long a, unsigned long b)
{
    if (a==b) return a;
    if (a>b) return cmmdc(a-b,b);
    return cmmdc(a, b-a);
}



unsigned long div(unsigned long k)
{ 
         unsigned long i,x;
         x=0;
         for (i=1; i<k; i++)
             if (cmmdc(i,k)==1) x++;
         return x;
}



unsigned long det(unsigned long n)
{
         unsigned long i,p;
         p=0;
         for (i=2; i<=n; i++)
          p=p+div(i);
         p=2*p+1;
         return p;
}



int main()
{
    FILE *f, *g;
    f=fopen("fractii.in","r");
    fscanf(f,"%lu",&n);
    g=fopen("fractii.out","w");
    fprintf(g,"%lu", det(n));
    return 0;
}