#include <stdio.h>
#include <stdlib.h>
FILE *f,*g;
int cmmdc(int a , int b)
{
    int r;
    while(b!=0)
    {
        r=a%b;
        a=b;
        b=r;
    }
    return a;
}
int main()
{
    int i,j,n,nr=0;
    f=fopen("fractii.in","r");
    g=fopen("fractii.out","w");
    fscanf(f,"%d",&n);
    for(i=1;i<=n;i++)
         for(j=i;j<=n;j++)
         {
                 if(cmmdc(i,j)==1)
                    nr+=2;
         }
    fprintf(g,"%d",nr-1);
    return 0;
}