#include<stdio.h>
int main () {
	int n,p,q,nr;
	FILE *in=fopen("fractii.in","r"), *out=fopen("fractii.out","w");
	fscanf(in,"%d",&n);
	nr=n-1;
	for(p=1;p<=n;p++)
		for(q=1;q<=n;q++)
			if((q==1)||((p%q!=0)&&(q%p!=0)))
				nr++;
	fprintf(out,"%d\n",nr);
	fclose(in);
	fclose(out);
	return 0;
}