Create deferred Query Execution with external method in CSharp

using System;//from  w w w  .j av  a  2  s.co m
using System.Linq;

class MainClass {
    static double Square(double n) {
        return Math.Pow(n, 2);
    }
    public static void Main() {
        int[] numbers = { 1, 2, 3 };
        var query = from n in numbers select Square(n);
        foreach (var n in query)
            Console.WriteLine(n);
    }
}