#include <fstream.h>

long int ss,i,j,n;

long int dd(long int x, long int y){
	    long int r,a=x,b=y;

	    do{r=a%b;a=b;b=r;}while(r);

	    return a;
}


int main(){
	   ifstream f("fractii.in");
	   ofstream g("fractii.out");


	   f>>n;
	   for(i=2;i<=n; i++)
	   for(j=1; j<=i-1; j++)
	   if(dd(i,j)>1)ss++;
	   g<<n*n-n+1-ss*2;

}