#include<stdio.h>
int main()
{long n,i,a,b,j,k,r,ok,min;
FILE *f=fopen("fractii.in","r");
FILE *g=fopen("fractii.out","w");
fscanf(f,"%ld",&n);
k=n*2-1;
for (i=2; i<=n; i++)
       for (j=2; j<=n; j++)
			{if (i<j) min=i;
			else min=j;
			ok=1;
			for (r=2;r<=min;r++) if (i%r==0&&j%r==0) {ok=0; break;}
			if (ok) k++;}

fprintf(g,"%ld",k);
 fclose(f);
 fclose(g);
 return 0;  }