The Light Bulb Sudoku

Today's puzzle is a riddle and then a sudoku (and both are brilliant!). It's called Light Bulb Moment by ZergreS and this is such an innovative idea, we're really blown away. You can play it at the following link:

https://app.crackingthecryptic.com/sudoku/JBNhmrn8dq

Rules:
Riddle: A long hallway has 43 light bulbs on the ceiling. Each light bulb has a pull cord that turns it on and off. All the lightbulbs start turned off. 43 people go down this hallway. The first person pulls every cord: 1,2,3,4... (now all bulbs are on) The second person pulls every other cord: 2,4,6,8... The third person pulls every third cord: 3,6,9,12... And so on with the rest. Finally the 43rd person pulls cord 43. Which bulbs are on after all the people have passed through? Feel free to use the Sudoku Grid to work out the answer.
Sudoku: Mark the final lit up bulbs in the Sudoku grid. (The hallway starts with Bulb 1 in R1C3) Lit hallway cells are brighter (higher) than their hallway neighbors. Hallway cells get darker (lower) as you get further away from a lit cell. Between every two lit cells in the hallway there will be a darkest (lowest) cell. It can be anywhere between the two lit cells. Arrows show the way through the hall. Digits along an arrow sum to the circled digit.

*** Our Book ***
The PDF is available as of today and the physical copy shouldn't be far behind. If you don't own the book then it can still be ordered here:
https://www.kickstarter.com/projects/peterchayward/cracking-the-cryptics-greatest-hits/

*** Our Patreon - The Best Sudoku Club In The World ***
You can join us on Patreon for as little as $2/month and access a lot of extra content. November's reward is a Japanese Sum Sudoku Extravaganza from Panthera and TheAsylm where every puzzle creates a picture! Finish all 45 puzzles and send us the password for the "Degree" file for a chance to win a prize.

https://www.patreon.com/crackingthecryptic

▶ SUDOKU PAD - Our New App ◀
You can now input your own classic sudoku puzzles into our software using our new App! The app also comes with 12 handmade puzzles from us and we're also releasing occasional bonus puzzles too. Get SudokuPad at these links:

iOS:
https://apps.apple.com/us/app/svens-sudokupad/id1570622073

Android:
https://play.google.com/store/apps/details?id=com.svencodes.sudokupad

**************************************************************

▶ OUR ARROW SUDOKU APP IS OUT ON ALL PLATFORMS!
Here are the links:
Steam:
https://store.steampowered.com/app/1613680/Arrow_Sudoku/
App Store:
https://apps.apple.com/us/app/arrow-sudoku/id1568407537
Google Play:
https://play.google.com/store/apps/details?id=com.StudioGoya.ArrowSudoku

▶ OUR KILLER SUDOKU APP IS OUT ON ALL PLATFORMS◀
https://apps.apple.com/us/app/killer-sudoku-ctc/id1544165118

https://store.steampowered.com/app/1471910/Killer_Sudoku/
https://play.google.com/store/apps/details?id=com.StudioGoya.KillerSudoku&hl=en_US&gl=US

▶ SIMON REACTION BOARD (!) ◀
With thanks to Andrea for creating this :)
https://simonreacts.avris.it/

▶ CTC FAN DISCORD SERVER◀
https://discord.gg/BbN89j5

NEW: Guide To Our Discord Server:
https://tinyurl.com/CTCDiscordGuide

▶ OUR BACK CATALOGUE – ALL CATEGORISED WITH LINKS!◀
https://tinyurl.com/CTCCatalogue

▶ *NEW* CRACKING THE CRYPTIC MERCHANDISE◀
https://teespring.com/en-GB/stores/cracking-the-cryptic

▶ OUR CHESS SUDOKU APP IS NOW OUT!◀
AppStore: https://apps.apple.com/us/app/chess-sudoku/id1500654482?ls=1
Steam: https://store.steampowered.com/app/1250560/Chess_Sudoku/
Android: https://play.google.com/store/apps/details?id=com.StudioGoya.ChessSudoku&hl=en_US

▶TRY OUR CLASSIC SUDOKU APP◀
AppStore: https://apps.apple.com/us/app/classic-sudoku/id1488838275?ls=1
Steam: https://store.steampowered.com/app/1188330/Classic_Sudoku/
Android: https://play.google.com/store/apps/details?id=com.StudioGoya.ClassicSudoku&hl=en_US

▶TRY OUR SANDWICH SUDOKU APP◀
AppStore: https://apps.apple.com/us/app/sandwich-sudoku/id1476116705?ls=1
Steam: https://store.steampowered.com/app/1117310/Sandwich_Sudoku/
Android: https://play.google.com/store/apps/details?id=com.StudioGoya.SandwichSudoku

▶SEND US PUZZLES TO SOLVE/CONTACT US◀
crackingthecryptic@gmail.com

▶FOLLOW US◀
Twitter: #crypticcracking
@crypticcracking
Instagram (for how to solve daily clues from The Times): https://www.instagram.com/crackingthecryptic/?hl=en

▶SOFTWARE◀
Play the puzzle in the video by clicking the link under the video (above). We are building a website which will allow you to enter your own sudoku puzzles into the software and this is coming soon!

▶Logo Design◀
Melvyn Mainini

▶ABOUT US◀
Hi! We're Simon Anthony and Mark Goodliffe, two of the UK's most enthusiastic puzzle solvers. We have both represented the UK at the World Sudoku Championships and the World Puzzle Championships.

Thank you for watching!
Simon and Mark

Видео The Light Bulb Sudoku канала Cracking The Cryptic