Matrix Output

/*
 * Write a program that reads from the console a positive integer number N (N < 20) and outputs a matrix
 */

using System;

class MatrixOutput
{
    static void Main()
    {
        byte numberN;
        string invalidInput = "Please enter a valid number 0 < N < 20!" + Environment.NewLine;
        Console.WriteLine("Enter a value for N: ");
        while (!(byte.TryParse(Console.ReadLine(), out numberN) && numberN > 0 && numberN < 20))
        {
            Console.WriteLine(invalidInput);
            Console.WriteLine("Enter a value for N: ");
        }
        Console.WriteLine();
        for (int j = 0; j < numberN; j++)
        {
            for (int k = 1; k <= numberN; k++)
            {
                Console.Write("{0,5} ", k + j);
            }
            Console.WriteLine();
        }
        Console.WriteLine();
        Main();
    }
}