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A comment on Seven Puzzles You Think You Must Not Have Heard Correctly (2006) [pdf].

Re:Seven Puzzles You Think You Must Not Have Heard Correctly... by mgillett on Monday August 29, 2016 @10:35AM (#12382092)
One that I heard last week: There is an 8x8 checkerboard in a room with a coin placed on each square. Each coin is either facing heads or tails up, and the face is determined randomly. Before you can inspect the board, a "master" comes in, picks a square of interest, and must make a manipulation to the board by flipping one of the 64 coins. He then exits the room. You are now allowed to enter, and must read out which square of interest the master chose by inspecting the state of the board. There is a strategy that is guaranteed to work for all possible configurations of the board.
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Re:Seven Puzzles You Think You Must Not Have Heard Correctly... by agf on Monday August 29, 2016 @10:49AM (#12382182)
I think you're referring to this puzzle: http://datagenetics.com/blog/december12014/index.html

The version you gave is missing information and so can't be solved as stated.

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Re:Seven Puzzles You Think You Must Not Have Heard Correctly... by kristjansson on Monday August 29, 2016 @12:33PM (#12383053)
Thank you for posting this. I read the parent several times trying to figure out if they were mistaken or I was dense.
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Re:Seven Puzzles You Think You Must Not Have Heard Correctly... by CPLX on Monday August 29, 2016 @11:03AM (#12382282)
I had to read that like 11 times before I started to get the underlying principle. That's amazing.
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Re:Seven Puzzles You Think You Must Not Have Heard Correctly... by hexane360 on Monday August 29, 2016 @05:59PM (#12385760)
In a very similar vein, try this one: https://youtu.be/N5vJSNXPEwA
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Re:Seven Puzzles You Think You Must Not Have Heard Correctly... by dpark on Monday August 29, 2016 @10:48AM (#12382180)
Either I'm somehow missing some critical piece of this puzzle or your description is. The master could pick a square at random, leaving you with a board (and likelihood of success) that is still completely random.

Are you supposed to be collaborating with the "master"?

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