This question already has an answer here:

There is a lot of fuzz about this Cheryls Birthday thing - and I understood the solution after a couple of deeper thoughts about it.

But what I am more interested in is; is the puzzle solvable using a form of formal logic?

During university (CS) I had many courses about formal logic and love the concept of wiriting down statements, and actually calculating a logical answer to it.

Is this doable with the infamous Cheryls Birthday puzzle?

Edit: Please note that I do not need an explanation of the puzzle, the solution, or how and why the participants can or can not say what they say. I am specifically looking for a solution that uses formal logic.


marked as duplicate by Ian MacDonald, leoll2, Volatility, kaine, Tryth Apr 20 '15 at 12:00

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    $\begingroup$ I don't explicitly use formal logic symbols, but this is solved using logic: puzzling.stackexchange.com/a/12318/10399 $\endgroup$ – Ian MacDonald Apr 20 '15 at 10:45
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    $\begingroup$ Look specifically at the Epilogue in the answer I already linked you. + is AND, = is IMPLIES. If this does not satisfy you, apply your own CS training to refine it. $\endgroup$ – Ian MacDonald Apr 20 '15 at 11:14
  • $\begingroup$ @IanMacDonald Sorry, I just now saw the epilogue. Must have skipped it when I skimmed the answers on the question. Looks close enough, thanks :-) $\endgroup$ – Florian Peschka Apr 20 '15 at 11:18
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    $\begingroup$ I love duplicates of duplicates of duplicates $\endgroup$ – leoll2 Apr 20 '15 at 11:30