using System;

using System.Linq;

​

public class Program

{

    public static void Main()

    {

        var ints = new [] { 1,2,5,9,10 };

        var trippleevens =  (from item in 

                                (from item in ints 

                                where item % 2 == 0 

                                select new { itemIn = item, itemOut = item * 3 } ).Concat

                                (from item in ints 

                                where item % 2 != 0 

                                select new { itemIn = item, itemOut = item })

                             orderby item.itemIn

                             select item.itemOut);

        foreach(var item in trippleevens)

            Console.WriteLine(item);

    }

}