#include "stdio.h"


unsigned int cmmmdc(unsigned int a, unsigned int b){
	unsigned int r;
	while (b) {
        r = a % b;
        a = b;
        b = r;
    }
    return a;
}

int main(){
	
	unsigned int x;
	unsigned int sol = 0;
	unsigned int i,j;
	FILE *f = fopen("fractii.in","r");
	
	fscanf(f,"%d",&x);
	
	for(i = 2; i<=x;i++){
		for(j = 2;j<=i;j++){
			if(cmmmdc(i,j) == 1){
				sol+=2;
			}
		}
	}
	
	fclose(f);
	
	sol = sol + 2 * x - 1;
	f = fopen("fractii.out","w");
	fprintf(f,"%d",sol);
	fclose(f);
	return 0;
}