#include <stdio.h>
FILE *in, *out;
int cmmdc(int a, int b)
{
	int c;
	while(c=a%b)
	{ a=b; b=c; }
	return b;
}
int main(void)
{
	int N,P,Q,T;
	in = fopen("fractii.in", "r");
	out = fopen("fractii.out", "w");
	fscanf(in, "%d", &N);
	T=N*2-1;
	for(P=2; P<=N; P++)
		for(Q=2; Q<=N; Q++)
			if(cmmdc(P,Q) == 1)
				T++;
	fprintf(out, "%d", T);	
	fclose(in);
	fclose(out);
	return 0;
}