[math-fun] Nice chess problem
Recently Noam Elkies showed me the following cute chess problem. I don't know if it is original with him. Normal starting position for Chess. Remove Black's King's Knight, and White's King's Knight and King's and Queen's pawns. White has just played her 5th move in a normal play of Chess. What was it? R.
Richard Guy wrote:
Recently Noam Elkies showed me the following cute chess problem. I don't know if it is original with him.
I will note that it is one of 41 ply-9 uniquely realizable (A102784) "at home" positions determined by Francois Labelle & computer, January 24, 2004: http://wismuth.com/chess/diagrams/at-home09-sol1.txt
Richard Guy wrote:
Normal starting position for Chess. Remove Black's King's Knight, and White's King's Knight and King's and Queen's pawns. White has just played her 5th move in a normal play of Chess. What was it?
Spoiler alert! Most players will soon realize that black's first move need be Nf6, and black's remaining three moves need to capture the two pawns and finally the knight (necessarily in row 1). But not the g1 knight it turns out, which executes the final Nxb1. The problem that remains is white possessing an extra extra ply. It took me a few minutes to realize that this can be "wasted" in white's first move!
If you like puzzles of this type you should definitely read Smullyan's brilliant collections _The Chess Mysteries of the Arabian Knights_ and _The Chess Mysteries of Sherlock Holmes_. If you search the web for smullyan chess you'll find a few samples lurking around. --Joshua Zucker On Sun, Mar 6, 2011 at 9:33 AM, Richard Guy <rkg@cpsc.ucalgary.ca> wrote:
Recently Noam Elkies showed me the following cute chess problem. I don't know if it is original with him.
Normal starting position for Chess. Remove Black's King's Knight, and White's King's Knight and King's and Queen's pawns. White has just played her 5th move in a normal play of Chess. What was it? R.
participants (3)
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Hans Havermann -
Joshua Zucker -
Richard Guy