#include <stdio.h>
 //Compiler version g++ 4.9

int getDivNr(int x){
	int sum = 0;
	for(int i = 2; i <= x/2; i++){
		if( x % i == 0){
			sum++;
		}
	}
	return sum;
}

 int main(void)
 {
 	FILE *in, *out;
 	int n, sub = 0;
 	in = fopen( "fractii.in", "r");
 	out = fopen( "fractii.out", "w");
 	
 	fscanf(in, "%d", &n);
 	
 	for( int i = 2; i < n; i++){
 		sub += getDivNr(i)  + n / i;
 	}
 	
 	fprintf(out, "%d", n * n - sub);
 	return 0;
 }