#include<fstream.h>
int main()
{
long int n,r,i,j,nr=0;
ifstream f("fractii.in");
f>>n;
f.close();
ofstream g("fractii.out");
nr=4*n-5;
for(i=2;i<=n-1;i++)
{
for(j=i+2;j<=n;j++)
{
if(i%2==0&&j%2!=0)
nr=nr+2;
else if(i%2!=0&&j%i!=0)
nr=nr+2;
}}
if(n>=10&&n%2==0)
g<<nr-2;
else
g<<nr;
g.close();
return 0;
}