using System;

using System.Linq;

public class Program

{

    static readonly byte[] THEGUID = new byte[16] {0x2a,0x78,0x8e,0x19,0x01,0xc3,0x5f,0x49,0xbb,0x97,0xf3,0xd9,0x95,0x75,0x9b,0x22};  

    private static Guid ToGuid(ulong changeTrackerId)

    {

        var bytes = BitConverter.GetBytes(changeTrackerId);

        byte[] result = (byte[])THEGUID.Clone();

        for(int i=0; i< bytes.Length; i++)

        {

            bytes[i] = (byte)((result[i] + bytes[i%8])%256);

        }

        return new Guid(result);

    }

    public static void Main()

    {

        ulong changeTrackerId = 10;     

        var guid = ToGuid(changeTrackerId);

        Console.WriteLine(guid);

    }

}