here's some fun analysis of septoku, a sudoku variant invented by bruce oberg that's played on a hexagon-tiled board ---------- Forwarded message ---------- From: Bruce Oberg <bruce@oberg.org> Date: Jan 4, 2008 4:20 PM Subject: septoku mother lode To: Thane Plambeck <tplambeck@gmail.com>, Nick Baxter <nickb@baxterweb.com>, Matt Scott <matt@loosecannonstudios.com>, Chris Zimmerman <chrisz@suckerpunch.com>, David Nixon <david@docnixon.com>, Amit Khetan <amitkhet@gmail.com>, David Moulton <moulton@idaccr.org> Cc: George Bell <gibell@comcast.net> hi y'all george bell has done a bunch of research into septoku, and produced some very interesting results. he's found that there are only 6 unique septoku boards (modulo substitution, rotation, and reflection). with this in hand, he's built some puzzles with only 6 seeds (they are very difficult to solve). i've posted his paper on my website: http://oberg.org/septoku_theorems.pdf with these results, all the questions i posed about septoku have been answered. george will claim $154 for answering questions #1 and #4 first. questions #2 and #3 had already been solved by earlier submissions: http://oberg.org/septoku_centers_proof.pdf (David Nixon) http://oberg.org/septoku_corners_proof.pdf (Amit Khetan and David Moulton) my original paper is here: http://oberg.org/septoku_g4g7.pdf thanks to everyone for spending some time on my little doodle. bruce oberg -- Thane Plambeck tplambeck@gmail.com http://www.plambeck.org/ehome.htm