#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int prime(int a,int b)
{int i;
if(a==b) return 0;
if (a>b)
    for(i=2;i<=b;i++)
       if((a%i==0)&&(b%i==0))return 0;
if (a<b)
    for(i=2;i<=a;i++)
       if((a%i==0)&&(b%i==0))return 0;
return 1;
}
int main ()
{
FILE *f,*g;
f=fopen("fractii.in","rt");
g=fopen("fractii.out","wt");   
int n;
fscanf(f,"%i",&n);
fclose(f);
int i,j,nr;
nr=n;
for (i=2;i<=n;i++)
    for (j=1;j<=n;j++)
        if(prime(i,j)==1) nr++;





fprintf(g,"%i",nr);
fclose(g);
}