#include<fstream>
using namespace std;
int main ()
{int n,i,j,k=1,l,x,y,m,p;
ifstream f("fractii.in");
ofstream g("fractii.out");
f>>n;
if(n>2)
{for(i=1;i<=n;i++)
{for(j=i+1;j<=n;j++)
{p=1;
x=i;
y=j;
if(x<y)
l=y;
else l=x;
for(m=2;m<=l;m++)
{   if(x%m==0 && y%m==0) 
p=0;}
if(p==1) 
k=k+2;}}}
else
{if(n==1) k=1;
else k=3;}
g<<k;
f.close();
g.close();
return 0;}