#include<stdio.h>      
#include<math.h>
long int n,p[50000],i,num,d,v,j,k;      
void ciur()      
{      
    d=2;      
  while (d<=n)      
  {      
   for (i=d+d; i<=n; i=i+d) p[i]=1;      
   d++;      
   while (p[d]==1) d++;      
  }      
}      
main()      
{      
  freopen("fractii.in","r",stdin);      
  freopen("fractii.out","w",stdout);      
  scanf("%ld",&n);      
  ciur();      
  num=n+n-1;      
  for (i=2; i<=n; i++)      
  {      
    for (j=2; j<=n; j++)      
    {      
      if (i<j)      
          if (j%i!=0)      
              if (p[i]==0) num++;      
              else     
              {v=1;      
              for (k=2; k<=sqrt(i); k++)      
                  if ((p[k]==0)&&(i%k==0)&&(j%k==0)){v=0; break;}      
              if (v==1) num++;      
              }      
            else;      
        else     
            if (i>j)      
                if (i%j!=0)      
                    if (p[j]==0) num++;      
                    else     
                    {      
                      v=1;      
                      for (k=2; k<=sqrt(j); k++)      
                          if ((p[k]==0)&&(i%k==0)&&(j%k==0)) {v=0; break;}      
                          if (v==1) num++;      
                    }      
    }      
  }      
  printf("%ld",num);      
}