Sunday 29 May 2016

Moving in Sequences

OMG! It took me 10 days!
Today is my late Mum's birthday and hence this blog post may be a little shorter than normal due to sadness and a visit by my brother. Today I am going to mention some puzzles that I have very little experience with and am really not very good - the group that I refer to in my personal classification as Sequential movement puzzles. Now you could argue that almost all puzzles are solved by sequences of movements and hence are ALL sequential movement puzzles and I do agree but that sort of argument is not really helpful. I know that a burr requires a set sequence but I still categorise it as a burr. The Gray code or N-ary group also is a sequential movement puzzle using a logical sequence but again that is not useful.

The photo above is Johan Heyns' production of Delirium 13 that I mentioned last week. Now we could argue the semantics of whether it is a burr, or an N-ary or a sequential movement puzzle but it doesn't help things much....I have called it a N-ary puzzle in my database. The difference now is that the photo shows the final position after the strict sequence of 5460 moves and after just one more I had this:

The relief on doing this was amazing!
This sequence of 5461 moves was absolutely based on a very logical sequence and it is impossible to go down a blind end. There are no branches or paths that lead you the wrong direction. So what is the difficulty? Well, as with almost all of this group, every position looks very similar to every other and when carrying out such a huge sequence, it is very easy to forget which move was just made and (especially after a pause or a pesky wife talking to you - Whack! Ouch! Sorry dear but it's true) it is perfectly easy to begin undoing what you had done and going back towards the beginning. I'm sure you all are thinking that only an idiot would get lost that easily in a single direction pathway and you are correct! I am not terribly bright and on 3 completely separate occasions I got about 2500 moves in to the pathway and in great excitement as I progressed, I suddenly found myself back at the beginning! It is a heartbreaking thing to do and to have done it 3 times just proves that I am rather stupid. But last night I was rude to Mrs S and wouldn't let her talk to me for much of the evening in front of the TV and with a huge shout after about 2 hours (that was my 3rd session over 3 evenings) I finally managed to get that first piece out. With the sheer size and weight of the puzzle I was exhausted and waited until today to take the rest of the pieces out (requiring just a further 12 moves for piece 2) and take my photos.

Johan made a MASTERPIECE!
It is a true work of art and I am so pleased to have it in my collection. It required such a huge effort that I doubt that I will be repeating it very often but I am sure that I'll have a go once or twice a year. As for resetting the puzzle..... I decided that this time I would explore the very clever reset mechanism that Johan made. In reality it was not intended for us - it was more for him so that in setting up the 12 that he made, he did not have to do them all in reverse!

The top comes off - he even provided an allen key in a wooden holder
The shuttle can be arranged perfectly
This one time to enjoy the process that Johan set up, I reset using his shortcut. Even that was not particularly easy as I needed to work out from my scrambled pieces how to arrange them to be reinserted in the puzzle!

Ready to go again? Maybe later!
IPP puzzle haul!
So where do I go from here? Now I move to some puzzles that I have actually categorised as sequential movement puzzles in my database. These particular puzzles are sliding tile puzzles and I have almost no experience of them. I met Diniar Namdarian at the London IPP and looked wistfully at his table of puzzles for sale but I had already spent such a fortune on puzzles (including Brian Young's Big Ben) that I really did not dare risk another Whack! Ouch! by buying yet more. Some time after the IPP I became friends with Diniar on Facebook and we communicated a bit. To my shame I only managed to buy some of his puzzles fairly recently and they have been sitting on my puzzles to pay with pile (annoying Mrs S) for a few weeks. I kept picking them up and attempting them but have to say that I really struggled! These puzzles are really tough and require some considerable concentration and a definite Aha! moment! Diniar is a true gentleman and settled on a very reasonable price for a batch of 4 puzzles and he threw in a few freebies which was very unexpected and very gratefully received.

Moon and Star
The first one I tried, at Diniar's suggestion, as relatively "easy" was his own design - the Moon and Star. The aim is to rearrange the pieces by sliding in the frame to make different configurations. You might wonder why this is tough - after all the 15 puzzle is pretty straightforward and has more pieces. This puzzle is made tougher by the fact that movement of one of the pieces is severely limited:

The top part of the moon protrudes from it's tile and cannot slide right
I received an emailed pdf with the challenges on it and began to play. I was seriously stuck for quite a while as I could get all the pieces in place but ended up needing 2 to be swapped over.....hmmmm! The aha! moment came because of my knowledge of twisty puzzles (also a sequential movement puzzle) and the fact that swapping 2 pieces is not possible. There had to be something more to it. Having worked out what the true requirement was I then had a plan of what to do. Even knowing what was required did not make it particularly easy and it still took me several hours before I was able to complete the full set of puzzles. Starting at position 1 above the aim is to go from this to other positions in sequence:

40 moves to Position 2
27 moves to Position 3
12 moves to Position 4

25 moves to Position 5
38 moves to Position 6
As an introduction to this group of puzzles, I really could not have asked for a better puzzle! This was a thoroughly enjoyable experience and even now if I try to repeat it then I have to think hard what to do and how to achieve it. This is suitable for beginners and kids alike. I am sure Diniar will be delighted to sell you one if you would like it.

One Fish, Another Fish
This puzzle was designed by the incredible Serhiy Grabarchuk who has also produced a phenomenal iOS puzzle game compendium called Puzzlium. As you can see above there is a fish with tail and fins in a tray formed by a 3x4 tile grid. The aim is to reverse the fish in direction and colour - easy right? Unfortunately (or maybe fortunately) it is NOT easy at all! Yet again there is a limitation of the movement this time caused by the curve of the corners of the tray:

The fins and tail pieces cannot be slid into the adjacent corners!
When I first began to play with this I managed to get to a position again where two pieces needed to be exchanged and my earlier Aha! moment was useful but getting around the restriction was proving very tough. After about 5 hours of attempts in total I managed to get to this position - yep! solved it!

Done it! Now to go back to the beginning.
Having managed this wonderful feat, I decided to work my way back to the start position by solving in reverse....except I cannot do it! I tried on and off for days and days and failed every time. At least with these puzzles, it is possible to pick up the tiles and start again when you get horribly lost. I have lost count of how many times I have had to start again. Thinking that it may have been a left vs right brain problem, I reset to the very beginning and tried to repeat my initial success and I cannot do it! I have absolutely no idea how I managed the puzzle the first time but I have not been able to repeat it again despite weeks of trying. This puzzle is fantastic value for money - I heartily recommend it. I still have 2 other puzzles left to do from Diniar but I really MUST solve this one first. I have to survive long enough however.....Mrs S gets upset with me mumbling to myself and shouting out expletives every time I fail!!!

You can contact Diniar via Facebook or you can contact me for his email address. I am sure that he will be delighted to sell you some of his wonderful toys! He may be a bit busy in the run up to the Japan IPP but I'm sure he will get back to you in time.


  1. Another great blog post Kevin, thanks. The sequential movement puzzles look really interesting and I have only left them to one side due to a chronic twisty addiction! Maybe it's time to have a closer look.

    1. Thanks Paul! Keep focussed on twisties - it will save you money in the long run! I'm addicted to everything and have storage and money problems as a result! At least these sequential movement puzzles are relatively cheap!

  2. I don't think I've completed a single n-ary without a serious mid-solve reversal. On the long ones, I think your brain just settles into auto-pilot mode, at which point you are in mortal danger. Hearbreaking is just the right word. Despiriting as well. I admire your resolve. That's over 20,000 moves you did on Delirlium!

    1. There's also the risk that if you start with the wrong piece then you cannot get to the end. Luckily I asked a friend which was the starting move before beginning! The 20,000 moves explains why I developed a callus on part of my middle finger!