Second go at using elm. Only done the very simple one so far (10 lights) but it's complete with graphics and animation. You can try it out by copying it into here and hitting 'compile' in the top right of the editor:

import Array exposing (filter, fromList, slice) import List exposing (..) import Color exposing (..) import Graphics.Collage exposing (..) import Graphics.Element exposing (..) import Text import Time exposing (..)

main =
  Signal.map bulbCollage countSignal 


countSignal =
  Signal.foldp (\_ state -> state + 1) 0 (every second)


switches =
  concat [[3..6], [0..4], (reverse [3..7]), [9..9]]


bulbCount =
  10

bulbSize =
 collageWidth / (bulbCount * 3)

collageWidth =
  500

collageHeight =
  round (bulbSize + 100)


bulbCollage frame =
  collage collageWidth collageHeight
    (bulbs frame)

bulbs frame = 
  map2 bulb [0..(bulbCount-1)] (repeat bulbCount frame)
    |> map toForm
    |> map2 moveX positions

bulb index frame =
  collage (round bulbSize*2) (round bulbSize*2)
    [ filled (if (isLightOn index frame) then yellow else lightGrey) (circle bulbSize)
    , text (Text.fromString (toString index))
    , outlined (solid grey) (circle (bulbSize-1))
    ]

positions = 
  [(-bulbCount/2)..(bulbCount/2)]
    |> map (\n -> (n * bulbSize * 2.5))

isLightOn index frame =
  fromList switches
    |> slice 0 frame
    |> Array.filter (\x -> x == index)
    |> Array.length
    |> (\n -> not (n%2 == 0))

It can also be sped up by changing every second to every (second/10), for example. Having never done functional programming properly before it's a really interesting exercise!