//#include <iostream.h>
#include <fstream.h>
#include <math.h>
int main()
{ifstream in("fractii.in");
ofstream out("fractii.out");
long s=0,n,a,b,r,u;
in>>n;
for (int i=4;i<=n;i++)
{u=0;
for (int j=2;j<i/2;j++)
{a=i;b=j;
while (b) {r=a%b;a=b;b=r;}
if (a!=1) u++;
}
s+=2*u;//cout<<u;
if (i%2==0) s++;
}
out<<n*n-n+1-2*s;
in.close();
out.close();
}