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Ponder This

April 2011

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Ponder This Challenge:

A wiggly plastic snake is composed of 20 segments. Assuming you start with a left turn, how many ways can the snake's other 18 joints be bent in 90-degree angles, either to the left or to the right, in such a way that the snake does not overlap/touch itself?

Thanks to Vi Hart for raising the question in her beautiful blog (link resides outside of ibm.com).

Bonus question: If you subtract the number of English letters from the answer, what is the connection of the result to the year 2010?


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Challenge: 04/01/2011 @ 01:00 PM EST
Solution: 05/02/2011 @ 11:30 AM EST
List Updated: 04/26/2011 @ 01:00 PM EST

People who answered correctly:

Daniel Bitin (04/01/2011 01:40 PM EDT)
Chidambaram Annamalai (04/01/2011 01:42 PM EDT)
Austin Shapiro (04/01/2011 03:01 PM EDT)
David Blackston (04/01/2011 03:58 PM EDT)
Joseph DeVincentis (04/01/2011 04:05 PM EDT)
Adam Daire (04/01/2011 05:17 PM EDT)
Shilei Zang (04/01/2011 05:48 PM EDT)
Tim Tran (04/01/2011 05:56 PM EDT)
Erik Postma (04/01/2011 06:30 PM EDT)
Motty Porat (04/01/2011 07:09 PM EDT)
Chuck Grant (04/01/2011 08:13 PM EDT)
Adam Hajari (04/01/2011 08:49 PM EDT)
Álvaro Begué (04/01/2011 09:25 PM EDT)
Victor Chang (04/01/2011 10:02 PM EDT)
Siyu Yang (04/01/2011 10:47 PM EDT)
Lu Wang (04/01/2011 11:33 PM EDT)
John T. Robinson (04/02/2011 12:00 AM EDT)
Nyles Heise (04/02/2011 12:19 AM EDT)
Mark Mixer (04/02/2011 06:51 AM EDT)
Emile Joubert (04/02/2011 08:48 AM EDT)
Federico de Ceballos (04/02/2011 02:21 PM EDT)
Chris Quayle (04/02/2011 02:38 PM EDT)
Matthew Paterson (04/02/2011 02:46 PM EDT)
Grant Stevens (04/02/2011 03:52 PM EDT)
Andrei Sipos (04/02/2011 04:12 PM EDT)
Balazs Ugron (04/02/2011 05:46 PM EDT)
Leif Jensen (04/02/2011 09:20 PM EDT)
Joshua Gunderson (04/02/2011 07:56 PM EDT)
Gary M. Gerken (04/02/2011 10:50 PM EDT)
Andreas Kabel (04/03/2011 04:35 AM EDT)
Nathanael Weldon (04/03/2011 06:01 AM EDT)
Piet Orye (04/03/2011 10:09 AM EDT)
Raúl Mora Pastor (04/03/2011 02:41 PM EDT)
Mathias Schenker (04/03/2011 04:01 PM EDT)
Harald van Dijk (04/03/2011 04:29 PM EDT)
Thijmen Krebs (04/03/2011 04:57 PM EDT)
Chris Shannon (04/03/2011 06:53 PM EDT)
Jonathan Campbell (04/03/2011 09:02 PM EDT)
Greg Janée (04/03/2011 09:03 PM EDT)
Rajendran Thirupugalsamy (04/03/2011 09:12 PM EDT)
Krunoslav Kovac (04/03/2011 11:51 PM EDT)
Blatter Christian (04/04/2011 09:54 AM EDT)
Mark Mammel (04/04/2011 12:59 PM EDT)
John Flavin (04/04/2011 02:33 PM EDT)
M. Zecevic (04/04/2011 02:46 PM EDT)
Phil Benamy (04/04/2011 03:09 PM EDT)
David Cole (04/04/2011 04:03 PM EDT)
Sandeep Rathour (04/04/2011 05:08 PM EDT)
James Wright (04/04/2011 05:59 PM EDT)
Matt Dobrin (04/04/2011 09:51 PM EDT)
Are Hjørungnes (04/04/2011 10:49 PM EDT)
Luke Pebody (04/05/2011 05:00 AM EDT)
Vincent Garnier (04/05/2011 07:20 AM EDT)
Panio Donev (04/05/2011 09:29 AM EDT)
Jonathon Noble Pendergrass (04/05/2011 12:02 PM EDT)
Dan Dima (04/05/2011 02:27 PM EDT)
David Friedman (04/05/2011 03:03 PM EDT)
Weichen Wang (04/05/2011 04:04 PM EDT)
Vitaly Ditman (04/06/2011 02:06 AM EDT)
Efthimios G. Karadimas (04/06/2011 08:02 AM EDT)
Miss Shawn Simpson (04/06/2011 03:44 PM EDT)
John Tromp (04/06/2011 08:13 PM EDT)
Anoop Ghanwani (04/06/2011 11:11 PM EDT)
John Duffield (04/07/2011 05:49 AM EDT)
Kurt Hectic (04/07/2011 07:14 AM EDT)
Danny Lynch (04/07/2011 09:02 AM EDT)
Benjamin Bachmann (04/07/2011 09:18 AM EDT)
Clive Tong (04/07/2011 02:22 PM EDT)
Jan Fricke (04/07/2011 04:30 PM EDT)
Sylvain Becker (04/07/2011 04:36 PM EDT)
Jamie Niemasik (04/07/2011 11:19 PM EDT)
Rick Kaye (04/08/2011 01:34 AM EDT)
David Gower (04/08/2011 11:25 AM EDT)
Donald T. Dodson (04/08/2011 01:06 PM EDT)
Armin Krauss (04/08/2011 02:50 PM EDT)
Vernon W. Miller (04/08/2011 08:17 PM EDT)
Sridivakar Inakonda (04/08/2011 10:57 PM EDT)
Andrea Andenna (04/09/2011 06:28 PM EDT)
William Heller (04/10/2011 11:16 AM EDT)
Sarthak Bagaria (04/10/2011 12:32 PM EDT)
John G. Fletcher (04/10/2011 07:52 PM EDT)
Stanislav Grudnitskiy (04/11/2011 12:35 AM EDT)
Jason Crease (04/11/2011 07:00 AM EDT)
Viacheslav Chernoy (04/11/2011 08:00 AM EDT)
Liubing Yu (04/12/2011 02:56 PM EDT)
Daniel Camero (04/12/2011 06:24 PM EDT)
Christian Pape (04/12/2011 06:39 PM EDT)
Bhavaji Sravani (04/12/2011 09:38 PM EDT)
Albert Stadler (04/13/2011 03:27 AM EDT)
Stéphane Higueret (04/13/2011 08:50 AM EDT)
Joe Riel (04/13/2011 12:43 PM EDT)
Ariel Flat (04/13/2011 03:10 PM EDT)
You Peijie
(04/14/2011 10:00 AM EDT)
Gale Greenlee (04/15/2011 12:41 PM EDT)
Miguel Cuartas Hernández (04/15/2011 09:04 PM EDT)
Varun V. Vasista (04/16/2011 04:14 AM EDT)
Stéphane Higueret (04/16/2011 05:30 AM EDT)
Ehud Schreiber (04/17/2011 04:06 AM EDT)
Aliaksei Sanko (04/17/2011 09:27 AM EDT)
Sumanth Prabhu S (04/18/2011 02:37 PM EDT)
Phil Muhm (04/18/2011 02:48 PM EDT)
John Snyder (04/18/2011 04:46 PM EDT)
Javier Rodríguez (04/19/2011 11:01 AM EDT)
Amos Guler (04/20/2011 08:02 AM EDT)
Dustin Shively (04/20/2011 02:13 PM EDT)
Siddharth S. (04/22/2011 10:19 AM EDT)
Jens Koesling (04/25/2011 09:21 AM EDT)
Nick Vigo and Kipp Johnson (04/26/2011 10:06 AM EDT)
Robin Chandra (04/26/2011 10:38 AM EDT)
Henry Wong (04/26/2011 02:40 PM EDT)
Toncean Adrian (04/27/2011 04:43 AM EDT)
Taher Jamshidi & Arash Bahrami (04/27/2011 02:12 PM EDT)
Chuck Carroll (04/27/2011 09:46 PM EDT)
Mutaamba Maasha (04/28/2011 08:13 AM EDT)
Rafael Casado Sánchez (04/28/2011 10:59 PM EDT)
Vivek Nema (04/29/2011 02:59 AM EDT)
Fabio Michele Negroni (04/30/2011 03:50 PM EDT)
Ante Kovacic (04/30/2011 05:43 PM EDT)
Antonio García Astudillo (05/01/2011 08:58 AM EDT)


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