#include <fstream.h>
#include <math.h>
ifstream f("fractii.in");
ofstream g("fractii.out");

long long n,x,i,j;
bool uz[1000001];
unsigned long long S=0;

main(){
	f>>n;
	x=n-2;
	S=2*n-1+2*(n/2+n%2-1)*abs(log2(n));
	uz[1]=uz[2]=1;
	for(i=4;i<=n;i*=2,x--)
		uz[i]=1;
	for(i=3;x>0;i++){
		if(uz[i])
			continue;
		for(j=i;j<=n;j*=i,x--)
			uz[j]=1;			
		S+=2*x;}
	g<<S;}