Matrix of Palindromes (with array)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApplication4
{
    class Program
    {
        static void Main(string[] args)
        {
            int rows = int.Parse(Console.ReadLine());
            int cols = int.Parse(Console.ReadLine());
            char mainCharacter;
            string alphabet1 = "abcdefghijklmnopqrstuvwxyz";
            char[] alphabet = alphabet1.ToArray();
            char helpCharacter;
            string[,] matrix = new string[rows, cols];
            for (int row = 0; row < matrix.GetLength(0); row++)
            {
                for (int col = 0; col < matrix.GetLength(1); col++)
                {
                    string output = string.Empty;
                    mainCharacter = alphabet[row];
                    helpCharacter = alphabet[col + row];
                    string outMain = mainCharacter.ToString();
                    string outHelp = helpCharacter.ToString();
                    output += mainCharacter;
                    output += helpCharacter;
                    output += mainCharacter;
                    output += " ";
                    matrix[row, col] = output;

                }

            }

            for (int i = 0; i < matrix.GetLength(0); i++)
            {
                for (int j = 0; j < matrix.GetLength(1); j++)
                {
                    Console.Write(matrix[i, j]);
                }
                Console.WriteLine();
            }

        }
    }
}