#include"stdio.h"  
#include"stdint.h"
uint_fast64_t g,h,n,out,a[20000000]; 
uint_fast64_t fct(uint_fast64_t g,uint_fast64_t h)
{
              if(h>n){g++;h=2*g;}
              if(g<=n){a[h]-=a[g];fct(g,h+g);}
}  
int main ()   
{   
freopen ("fractii.in","r",stdin);   
freopen ("fractii.out","w",stdout);   
scanf ("%lld",&n);for (g=1;g<=n;g++)a[g]=g-1;    
fct(2,4);
for (g=1;g<=n;g++,out+=a[g]);   
printf ("%lld",2*out+1);   
return 0;   
}