6.15Loops_MatrixOfNumbersReverse

using System;

class MatrixOfNumbersReverse
{
    static void Main()
    {
        Console.Write("Enter a whole positive number in the range [1...20], for N = ");
        string numberStr = Console.ReadLine();
        int numN = int.Parse(numberStr);

        if (numN < 1 || numN > 20)
        {
            Console.WriteLine("Error - The Number is Out of Range !!!");
        }
        else
        {
            int[,] matrix = new int[numN, numN];
            Console.WriteLine("The Matrix of that number N is:");
            Console.WriteLine();
            for (int i = numN; i >= 1; i--)
            {
                for (int j = (i + numN - 1); j > (i - 1); j--)
                {
                    Console.Write("{0,4} ", j);
                }
                Console.WriteLine();
                Console.WriteLine();
            }
        }
        Console.ReadLine();
    }
}