FizzBuzz using nodes in a circle.

Program.cs

namespace FizzBuzzCircular;

using System.Collections;
using System.Collections.Generic;

class Program
{
    public class Node
    {
        private readonly Func<string> _fn;
        private Node _next;

        public Node(Func<string> fn) 
        {
            _fn = fn;
        }

        public Func<string> Value => _fn;

        public Node Next => _next;

        public Node Chain(Node next) 
        {
            _next = next;
            return next;
        }
    }

    public class FizzBuzzEnumerable : IEnumerable<string>
    {
        public IEnumerator<string> GetEnumerator()
        {
            return new FizzBuzzEnumerator();
        }

        IEnumerator IEnumerable.GetEnumerator()
        {
            return GetEnumerator();
        }
    }

    public class Numberator : IEnumerator<int> 
    {
        private int _n;

        public bool MoveNext()
        {
            ++_n;
            return true;
        }

        public int Current => _n;

        object IEnumerator.Current
        {
            get { return Current; }
        }

        public void Dispose() {}

        public void Reset() {}
    }

    public class FizzBuzzEnumerator : IEnumerator<string>
    {
        private Numberator _numberator;
        private Node _node;

        public FizzBuzzEnumerator() 
        {
            _numberator = new Numberator();
            var number = () => _numberator.Current.ToString();
            var fizz = () => "Fizz";
            var buzz = () => "Buzz";
            var fizzBuzz = () => "Fizz Buzz";
            _node = new Node(fizzBuzz);
            _node
            .Chain(new Node(number))
            .Chain(new Node(number))
            .Chain(new Node(fizz))
            .Chain(new Node(number))
            .Chain(new Node(buzz))
            .Chain(new Node(fizz))
            .Chain(new Node(number))
            .Chain(new Node(number))
            .Chain(new Node(fizz))
            .Chain(new Node(buzz))
            .Chain(new Node(number))
            .Chain(new Node(fizz))
            .Chain(new Node(number))
            .Chain(new Node(number))
            .Chain(_node);
        }

        public bool MoveNext()
        {
            _numberator.MoveNext();
            _node = _node.Next;
            return true;
        }

        public string Current => _node.Value();

        object IEnumerator.Current
        {
            get { return Current; }
        }

        public void Dispose() {}

        public void Reset() {}
    }

    static void Main(string[] args)
    {
        foreach (var s in new FizzBuzzEnumerable().Take(int.Parse(args[0]))) 
        {
            Console.WriteLine(s);
        }
    }
}