using System;

using System.Collections.Generic;

public class Program

{

    public static List<int> FirstNNaturalNumbers(int n)

    {

        List<int> listy = new List<int>{};

        if (n == 1)

        {

            listy.Add(1);

            return listy;

        }

        else

            return listy.AddRange(FirstNNaturalNumbers(n-1));

    }

    public static void Main()

    {

        Console.WriteLine(FirstNNaturalNumbers(5));

    }

}