Inside MI6's server farm in the middle of the night, the operator's eyes skittered frantically over an intercepted message:

The development of our new APG code has been coming along nicely; I've signed this message in it. Tomorrow you, under my supervision, will rig the random number generators – both mechanical and electronic – in the Paris casino so that anyone who comes gambling wins and the management will be forced to declare insolvency. Of course we will be reaping the lion's share.
In case you don't know APG code, basically you've got to play a game on your own, of births and deaths of cells specified in each line. The message is in the periods. One limitation is that we can't use S in messages, and until recently we couldn't use W either – but we can always work around.
I wish you the best of luck.

"By Golly!" Miss Moneypenny exclaimed; she had just arrived in the control room. "Is the last part of the decrypt correct?"

"Yes indeed," came the operator's reply, her voice trembling with a mixture of fear and excitement. "I can give you the details at a more convenient time, but James Bond has a new mission."

"We can talk later. Good night."

Who wrote the message?


2 Answers 2





The "birth and death of cells" makes this a Conway's Game of Life puzzle. APG code can be used to store a particular configuration of cells, some of which have names. Looking up the first line gave me what is known as the "Baker's Dozen". The period of the Baker's Dozen is 12. This gives us the letter "L". Continue solving for the other lines to get the solution. Translating APG into the game and seeing how many turns it takes to start it's "cycle" again is it's period.

Full list:

Baker's Dozen (12), Unnamed (5), 4 Blocks on Star (3), Tumbling T-Tetson (8), Snacker (9), T-Nosed P6 (6), Unnamed (6), P18 Bi-Block Hassler (18), and Unnamed (5)

  • $\begingroup$ @ParclyTaxel I've edited that link into the answer (found it shortly before you replied), but I'd still see the answer as missing several steps - specifically where and how were the given codes "looked up" as-is or what steps were taken to correctly regenerate the missing prefixes implied by the wiki page. $\endgroup$
    – Steve
    Jun 24, 2021 at 15:47

A partial answer only at this point, I am still working on this and hope to come back to it later!

My suspicion is that this relates to

Conway's Game of Life

More specifically, I think that

the 26 letters and 10 digits in the encoding encode 36 cells in a 6x6 arrangement. I suspect that each row of the signature encodes a starting arrangement (and a few of the subsequent births / deaths of cells) resulting in an oscillator with a different period. For example, an arrangement with period 3 would clue the letter C. I suspect that a starting arrangement with period 19 (S) hasn't been found and the arrangement for period 23 (W) was perhaps only found recently - this is backed up by information here: https://conwaylife.com/wiki/Oscillator

I need to do some more digging to find out how the characters would map to the square to make this work out and decode it.

Update: No matter which way out I label the squares (a-z0-9, 0-9a-z, etc) I can't quite make this work. The third line in the code is particularly intriguing:

consists of three palindromes:
3js46364sj3 / zhje8ogo8ejhz / 11x1x11

Given that cells can't die before they've been born, this seems to imply a set of symmetrical sets of births and deaths, which is unusual.

  • 3
    $\begingroup$ I am in fact the one who named the period-23 oscillator (David Hilbert), as well as other Life patterns like rattlesnake, syringe and lei. $\endgroup$ Jun 22, 2021 at 1:21

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