#include<stdio.h>
#include<stdlib.h>
int main()
{
	int n;
	int cate,i;
	FILE *f,*g;
	f=fopen("fractii.in","r");
	g=fopen("fractii.out","w");
	fscanf(f,"%d",&n);
	for(i=2,cate=0;i<=n;i++)
	{       int j;
		for(j=2;j<=n;j++){
			if(i%j!=0 && j%i!=0) {
			cate++;
//			fprintf(g,"%d %d\n",i,j);
				}
		}
	}
	fprintf(g,"%d",cate+2*n-1);
	fclose(f);
	fclose(g);

return 0;
}