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Timeline for The Erasmus rook tour

Current License: CC BY-SA 3.0

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Feb 14, 2015 at 19:13 vote accept Gamow
Feb 3, 2015 at 20:11 comment added Joel Rondeau @KSmarts I started with larger shapes that I'd have to join together. When I was trying to simplify that, I discovered that every one could be created from $2x2$ squares. Made the problem much simpler.
Feb 3, 2015 at 20:03 comment added KSmarts Okay, I get it. I was thinking along these same lines, but you beat me to it. Also, I wasn't sure if it covered all tours.
Feb 3, 2015 at 19:50 comment added Joel Rondeau @KSmarts Take 2 squares at A1:B2 and C1:D2. To join them together, you remove the vertical lines (moves) at B1:B2 and C1:C2 and replace them with horizontal lines (moves) at B1:C1 and B2:C2. The joining can always be the replacement of 2 vertical lines with 2 horizontal lines of a $2 x 2$ square (or 2 horizontal with 2 vertical lines).
Feb 3, 2015 at 19:41 comment added KSmarts I'm not sure what you mean here, by "when [joining 2 shapes], you will alter both the horizontal and vertical moves by 2."
Feb 3, 2015 at 19:22 comment added Joel Rondeau @Lopsy, I'm reasonably certain that every rook tour can be made this way for any $m x n$ board where $m$ and $n$ are both even.
Feb 3, 2015 at 19:13 comment added Lopsy Re your proof: not every possible rook tour can be made by joining 2x2 squares together, right?
Feb 3, 2015 at 18:58 history edited Joel Rondeau CC BY-SA 3.0
Included proof.
Feb 3, 2015 at 18:06 comment added KSmarts I'm in the same place as you. But, "I can't find one" doesn't mean, "there isn't one". I'm pretty sure there isn't, but I'm trying to prove it.
Feb 3, 2015 at 17:55 comment added Joel Rondeau I do not have a full proof for the 8x8 board. Given what I tried with the 4x4 and then 6x6 board and the fact that similar answers didn't get me any closer than 4 for the 8x8, I believe it to be correct. I'll see if I can put something together later.
Feb 3, 2015 at 17:51 comment added Trenin What is the proof for the 8x8 board?
Feb 3, 2015 at 17:47 history answered Joel Rondeau CC BY-SA 3.0