//	Read N from keyboard (even #)
// find the average of all odd # from 0, .. N?

import java.util.Scanner;
class ForLoop2mmm
{
	public static void main(String[] args)
	{
			Scanner input = new Scanner(System.in);
			int N = input.nextInt();
			int sum = 0;
			int size = 0; // # of items
			double avg;
			for ( int count=1; count<=N; count+=2 )
			{
					System.out.println(count);
					sum = sum + count;
					size ++;
			}
			avg = (double)sum / size;
			System.out.println("sum = " + sum);
			System.out.println("size = " + size);
			System.out.println("avg = " + avg);
	}
}