Nice, you can use any IEnumerable as the source for you LINQ queries.

class Program {
    static void Main(string[] args) {

         var result = from x in GetSequence(12) where (x%2) == 0 select x;

         foreach (var x in result) {
             Console.WriteLine(x);
         }

        Console.ReadLine();

    }

    static IEnumerable<int> GetSequence(int max) {

        for (int i = 0; i < max; i++) yield return i;

    }
}