[Retros] Self-protecting Chess puzzles

Eric Angelini Eric.Angelini at kntv.be
Wed Jan 23 10:18:08 EST 2008

Hello Retro-fans,
[this is my third msg to the list with the same concern;
I re-subscribed a few seconds ago because the two first
didn't show in my mail-box (nor in the archives). If this
is old hat, please forgive me. Here is my former 8/I msg.
Since then I've added a 64 US$ reward, somewhere on the


Hello Retro friends,
Start the year with this light idea:


Self-protecting Chess diagrams are legal chess positions with 8 white pawns, 8 white men and no black piece at all (but one empty square, at least, must be available for the Black King).

The SPC concept claims that every piece protects exactly one other piece and is protected by exactly one.

This can be achieved by one giant loop (like in diag.1), where A protects only B, which protects only C, which protects only D, etc. until P which protects only A (start with the Queen in a1 and check):


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