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

public class Dwite5q2
{
        public static int n; // input data ??
        public static int answer; // answer ??

        public static void main(String[] args) throws IOException
        {
                String infilename= "DATA2.txt";
                String outfilename="OUT2.txt";
                int nsets= 5; //number of sets in input file
                
                //Open in/output streams
                Scanner in = new Scanner(new FileInputStream(infilename));
                BufferedWriter out = new BufferedWriter(new FileWriter(outfilename));

                for (int i=0; i<nsets; i++)
                {
                        readdata( in );
                        calculate();
                        writedata( out );
                }
        
                //Close the in/output streams
                in.close();
                out.close();
        }

        //----------------------------------------------------------------
        //Read Data
        public static void readdata(Scanner in) throws IOException
        {
                 n = in.nextInt(); //nextInt, nextString, nextDouble, nextByte
        }

        //----------------------------------------------------------------
        //Calculate
        public static void calculate()
        {
        		answer=0;
                for(int i=1; i<=n; i++ )
                {
                	for(int j=1;j<=(int)(Math.sqrt(i));j++)
                	{
                		if(i%j==0)
                		{
                			answer++;
                		}
                	}
                }
        }

        //----------------------------------------------------------------
        //Write Data
        public static void writedata(BufferedWriter out) throws IOException
        {
                //float or double: %f, %5.1f, %.1f
                //int: %d, %6d
                //string: %s
                //%: %%
                out.write(answer+"\r\n");
        }
}