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Ponder This

June 2006

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Ponder This Challenge:

Puzzle for June 2006.

Suppose we use dominoes to tile an infinite strip of height 2. In a typical tiling what fraction of the dominoes will be oriented vertically?  Typical can be defined rigorously by considering all possible tilings of a 2*n rectangle and then letting n go to infinity.


The first 100 people who answer all parts correctly will be listed. The answer will be posted a week after the 100th is received, or at the end of the month.

We will post the names of those who submit a correct, original solution! If you don't want your name posted then please include such a statement in your submission!

We invite visitors to our website to submit an elegant solution. Send your submission to the ponder@il.ibm.com.

If you have any problems you think we might enjoy, please send them in. All replies should be sent to: ponder@il.ibm.com

  

Challenge: 06/01/2006 @ 10:00 AM EST
Solution: 06/30/2006 @ 03:00 PM EST
List Updated: 06/01/2006 @ 10:00 AM EST

People who answered correctly:

Kevin Costello (06.01.2006 @11:40:03 AM EDT)
Balakrishnan V (06.01.2006 @12:04:59 PM EDT)
Dan Dima (06.01.2006 @12:49:47 PM EDT)
Frank Yang (06.01.2006 @04:06:23 PM EDT)
Dinesh Krithivasan (06.01.2006 @04:58:04 PM EDT)
Jan Rubak (06.01.2006 @05:01:44 PM EDT)
Hagen von Eitzen (06.01.2006 @06:18:01 PM EDT)
David Vaccaro (06.01.2006 @08:20:58 PM EDT)
Steven Noble (06.01.2006 @08:21:41 PM EDT)
Luke Pebody (06.01.2006 @09:42:18 PM EDT)
lalafa1003 (06.01.2006 @09:48:13 PM EDT)
Graeme McRae (06.02.2006 @03:04:14 AM EDT)
Roberto Tauraso (06.02.2006 @07:35:08 AM EDT)
Kennan Shelton (06.02.2006 @09:25:17 AM EDT)
Harold Gutch (06.02.2006 @10:53:48 AM EDT)
Michael Brand (06.02.2006 @11:18:47 AM EDT)
Miroslava Sotakova (06.02.2006 @11:28:31 AM EDT)
Joël Bleuse (06.02.2006 @01:04:32 PM EDT)
Andrew McRae (06.02.2006 @03:20:14 PM EDT)
Eugene Vasilchenko (06.02.2006 @04:33:29 PM EDT)
Douglas Zare (06.02.2006 @05:43:16 PM EDT)
Alap Karapurkar (06.02.2006 @07:14:58 PM EDT)
Dion K Harmon (06.02.2006 @07:58:36 PM EDT)
James Dow Allen (06.03.2006 @01:35:46 AM EDT)
Manuel Gräf (06.03.2006 @12:13:43 PM EDT)
Chris Hills (06.03.2006 @01:32:01 PM EDT)
Vitaly Stakhovsky (06.03.2006 @02:22:14 PM EDT)
John Dalbec (06.03.2006 @03:59:18 PM EDT)
Gareth McCaughan (06.03.2006 @07:06:48 PM EDT)
John Hubenschmidt (06.04.2006 @12:43:31 AM EDT)
Andrey Goder (06.04.2006 @02:36:19 AM EDT)
Alexey Vorobyov (06.04.2006 @03:43:51 AM EDT)
Dan Pryor (06.04.2006 @08:45:01 AM EDT)
Joseph DeVincentis (06.04.2006 @12:11:49 PM EDT)
Ping-Che Chen (06.04.2006 @02:21:08 PM EDT)
Ed Sheppard (06.04.2006 @09:07:01 PM EDT)
Guangzhong Sun (06.04.2006 @11:36:41 PM EDT)
Alan Murray (06.05.2006 @01:16:05 AM EDT)
Roger Thompson (06.05.2006 @03:59:13 AM EDT)
Tristrom Cooke (06.05.2006 @05:29:23 AM EDT)
John Tromp (06.05.2006 @08:07:28 AM EDT)
Matthew Paterson (06.05.2006 @08:35:22 AM EDT)
Chris Lomont (06.05.2006 @01:57:15 PM EDT)
Se Kwon Kim (06.06.2006 @03:23:39 AM EDT)
Ben North (06.06.2006 @05:17:21 AM EDT)
Ashish Mishra (06.06.2006 @05:46:26 AM EDT)
David McQuillan (06.06.2006 @07:33:06 AM EDT)
Frank Schmidt (06.06.2006 @09:20:09 AM EDT)
Phil Muhm (06.06.2006 @01:29:00 PM EDT)
Kerry M Soileau (06.06.2006 @05:15:04 PM EDT)
William C Hasenplaugh (06.06.2006 @05:58:42 PM EDT)
Kirk Bresniker (06.06.2006 @07:34:38 PM EDT)
Wolf Mosle (06.06.2006 @08:10:26 PM EDT)
Biantaishabi (06.06.2006 @09:46:40 PM EDT)
Austin Shapiro (06.06.2006 @11:17:42 PM EDT)
Bart De Vylder (06.07.2006 @08:55:35 AM EDT)
Thijs Veugen (06.07.2006 @09:36:02 AM EDT)
Chuck Carroll (06.07.2006 @09:39:04 AM EDT)
Andrew Buchanan (06.07.2006 @09:56:00 AM EDT)
Christian Blatter (06.07.2006 @10:51:24 AM EDT)
Alex Izvalov (06.08.2006 @02:38:01 PM EDT)
David Friedman (06.08.2006 @02:43:15 PM EDT)
Ramkumar Balaraman (06.08.2006 @08:07:58 PM EDT)
Eric R. Farmer (06.09.2006 @09:46:26 AM EDT)
Emilio Schiavi (06.09.2006 @01:52:32 PM EDT)
Du Yang (06.09.2006 @02:30:08 PM EDT)
Brendan Owen (06.10.2006 @02:18:19 AM EDT)
Chuck Nelson (06.10.2006 @12:20:58 PM EDT)
Wolf Mosle (06.11.2006 @12:31:27 AM EDT)
Edna Mantsour (06.11.2006 @09:27:50 AM EDT)
Jan Van Delden (06.11.2006 @02:15:11 PM EDT)
Narayanan Rajamani (06.11.2006 @06:18:06 PM EDT)
Mohammed Ajmal (06.11.2006 @07:24:15 PM EDT)
Pushkar S. Joglekar (06.12.2006 @06:28:37 AM EDT)
Zhou Guang (06.12.2006 @09:05:42 PM EDT)
Firat Solgun (06.13.2006 @04:45:11 PM EDT)
Richard A Bauer (06.14.2006 @12:56:34 AM EDT)
Jack Kennedy (06.14.2006 @01:30:56 PM EDT)
Robin Ryder (06.15.2006 @10:23:31 AM EDT)
John G. Fletcher (06.15.2006 @04:27:32 PM EDT)
Clive Tong (06.16.2006 @07:04:11 AM EDT)
John Roy (06.16.2006 @11:37:59 AM EDT)
Federico Felizzi (06.19.2006 @02:40:39 AM EDT)
Ariel Flat (06.19.2006 @02:47:39 AM EDT)
Vince Lynch (06.19.2006 @07:07:43 PM EDT)
Jiri Hrdina (06.21.2006 @08:02:34 AM EDT)
Van Steirteghem Anneke (06.21.2006 @09:42:26 AM EDT)
Greg Bubnis (06.21.2006 @09:57:19 AM EDT)
Ervan Darnell (06.21.2006 @06:58:06 PM EDT)
Leo Broukhis (06.21.2006 @10:34:44 PM EDT)
Yoav Raz (06.22.2006 @10:18:50 PM EDT)
Greg Janée (06.23.2006 @03:26:16 AM EDT)
Jonathan Mizrahi (06.27.2006 @08:25:21 AM EDT)
Christopher Reed (06.29.2006 @08:04:02 AM EDT)


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