C# - LINQ - Recursive

//C# program that uses recursive method
using System;
using System.Collections.Generic;
using System.Linq;
 
class Program
{
    static void Main()
    {
        // ... Call recursive method directly.
        List<int> list = new List<int>();
        X(list, 0);
 
        // ... Verify sum.
        Console.WriteLine(list.Sum());
    }
 
    static void X(List<int> list, int value)
    {
        if (list.Count < 10)
        {
            list.Add(value);
            X(list, value + 1);
        }
    }
}
 
 
//C# program that inlines recursive call
using System;
using System.Collections.Generic;
using System.Linq;
 
class Program
{
    static void Main()
    {
        // ... Inline first recursive call.
        List<int> list = new List<int>();
        if (list.Count < 10)
        {
            list.Add(0);
            X(list, 0 + 1);
        }
 
        // ... Verify sum.
        Console.WriteLine(list.Sum());
    }
 
    static void X(List<int> list, int value)
    {
        if (list.Count < 10)
        {
            list.Add(value);
            X(list, value + 1);
        }
    }
}