/*Yi and YUXIN*/

import java.util.Scanner;
import java.io.*;


public class Problem2{
		static int num,a, cnt;
	public static void main (String[] args) throws Exception{     
		

				
		Scanner sc = new Scanner(new File("DATA2.txt"));   
		PrintWriter out = new PrintWriter(new BufferedWriter(new FileWriter("OUT2.txt")));  		
		while(sc.hasNext()){
			num = sc.nextInt();
			cnt=0;
			for(int t=1;t<=num;t++){
					
				cnt+=factor(t);	
				
			}
			//System.out.println(cnt);
					out.println(cnt);
			}
			
		sc.close();
		out.close();
		System.exit(0);	
		}
			public static int factor(int b){
				int cc=0;
				a=(int)(Math.sqrt(b));
				for (int i=1; i<=a; i++){
					cnt=0;	
					if(b%i==0){
						cc++;
						}
				
				}
				return cc;
			}

}