gistfile1.cs

using System;

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            int x = 4;
            int y = 6;

            printGrid(x, y);

            Console.Read();
        }

        static void printGrid(int x, int y)
        {
            for (int a = 1; a <= x; a++)
            {
                var val = a; // this is what you are missing
                Console.Write(val + " ");

                for (int b = 1; b < y; b++)
                {
                    val = val + x;
                    Console.Write(val + " ");
                }

                Console.WriteLine();
            }
        }
    }
}