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Ponder This

October 2009

<<September October November>>


Ponder This Challenge:

Complete the following sequence:

1, 13, 2, 1, 5, 3, 2, 1, 4, 4, 7, 3, 1, 5, 3, 5, ?, ?

Beware - this month's challenge is different than usual.

Hint (10/07): The solution is related to a quote about mathematicians.


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 webmaster.

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

  

Challenge: 10/01/2009 @ 15:00 PM EST
Solution: 11/02/2009 @ 15:00 PM EST
List Updated: 11/04/2009 @ 15:00 PM EST

People who answered correctly:

Tony Maric (10/01/2009 07:35 PM EDT)
Albert Stadler (10/02/2009 08:11 AM EDT)
ICM, Univ. of Warsaw (10/02/2009 08:46 AM EDT)
Andreas Stiller (10/07/2009 01:44 PM EDT)
Harald Bögeholz (10/07/2009 01:37 PM EDT)
Dan Dima (10/07/2009 02:10 PM EDT)
Mark Mixer (10/07/2009 02:26 PM EDT)
Tom Sirgedas (10/07/2009 03:22 PM EDT)
Alan B. (10/07/2009 04:01 PM EDT)
John T. Robinson (10/07/2009 04:56 PM EDT)
Beryl Schragger (10/07/2009 05:16 PM EDT)
David Challener (10/07/2009 06:26 PM EDT)
Jeff Blohm (10/07/2009 07:33 PM EDT)
Alexander Wagner (10/07/2009 09:21 PM EDT)
Nyles Heise ( 10/07/2009 11:16 PM EDT)
pulsar (h.nathen) (10/07/2009 11:18 PM EDT)
Tulasi Ram Reddy A (10/08/2009 02:15 AM EDT)
Thursday Next (10/08/2009 02:26 AM EDT)
Ben Tarlow (10/08/2009 05:44 AM EDT)
L. Sabarathinam (10/08/2009 06:04 AM EDT)
Arovit Narula (10/08/2009 06:53 AM EDT)
Joseph Bonneau (10/08/2009 10:29 AM EDT)
Alexander Ivrii (10/08/2009 10:34 AM EDT)
Ioan Marius Popdan (10/08/2009 11:34 AM EDT)
Yuval Filmus (10/08/2009 11:57 AM EDT)
Kin Keung Ma (10/08/2009 12:04 PM EDT)
Irem Koprulu (10/08/2009 02:10 PM EDT)
Clive Tong (10/08/2009 02:12 PM EDT)
Greg Janée (10/08/2009 02:16 PM EDT)
Martin Thiim (10/08/2009 02:44 PM EDT)
Satish Kumar K N (10/08/2009 03:34 PM EDT)
Christian Kissig & Rick Thomas (10/08/2009 04:08 PM EDT)
Phil Muhm (10/08/2009 04:43 PM EDT)
Mihai Cioc
(10/08/2009 06:26 PM EDT)
Karthik Gnanamurthy
(10/08/2009 07:25 PM EDT)
Chuck Grant
(10/08/2009 09:59 PM EDT)
Zhou Guang
(10/08/2009 11:27 PM EDT)
Ivan Sobotik (10/09/2009 02:01 AM EDT)
Shmuel Menachem Spiegel (10/09/2009 02:11 AM EDT)
David Friedman (10/09/2009 02:24 AM EDT)
L. J. Zigerell Jr. (10/09/2009 02:47 AM EDT)
Mithil Ramteke (10/09/2009 03:14 AM EDT)
Caroline Boucaut (10/09/2009 06:37 AM EDT)
Tejaswi Navilarekallu (10/09/2009 07:33 AM EDT)
Andrew J. Gambier (10/09/2009 07:51 AM EDT)
William G. Hunter (10/09/2009 08:35 AM EDT)
Guillaume de Longeaux (10/09/2009 09:33 AM EDT)
David Englund (10/09/2009 09:44 AM EDT)
Panio Donev (10/09/2009 11:45 AM EDT)
David Zimmermann (10/09/2009 12:09 PM EDT)
Christian Blatter (10/09/2009 12:12 PM EDT)
Udit Narayan Sharma (10/09/2009 01:22 PM EDT)
Mark Abramson (10/09/2009 01:40 PM EDT)
Bojan Basic (10/09/2009 02:21 PM EDT)
Frank Vernaillen (10/09/2009 04:35 PM EDT)
Ante Turudic (10/09/2009 04:50 PM EDT)
Marek Krzysztof Misztal (10/09/2009 06:35 PM EDT)
Victor Chang (10/09/2009 06:45 PM EDT)
Hendrik Krauß (10/09/2009 09:26 PM EDT)
Prithwijit De (10/09/2009 11:35 PM EDT)
Hyeshik Chang (10/10/2009 07:46 AM EDT)
Josh Matthews (10/10/2009 12:16 AM EDT)
Erick Wong (10/10/2009 02:55 PM EDT)
Farid Lian (10/10/2009 03:36 AM EDT)
Robert Szafranski (10/10/2009 06:47 PM EDT)
Marcin S. (10/10/2009 06:49 PM EDT)
Deepti Agrawal (10/11/2009 02:03 AM EDT)
Sen Gu (10/11/2009 02:11 EDT)
Hoang Nguyen (10/11/2009 03:37 AM EDT)
Ingrid Voigt (10/11/2009 11:31 AM EDT)
Corey Cerovsek (10/11/2009 07:13 PM EDT)
Subramanian C. A (10/12/2009 01:27 AM EDT)
Dan Ungureanu (10/12/2009 07:21 AM EDT)
Abhiram R Devesh (10/12/2009 08:48 AM EDT)
Inbal Shafran (10/12/2009 10:00 AM EDT)
Wooyoung Chin (12/10/2009 11:06 AM EDT)
Federico Felizzi (10/12/2009 11:18 AM EDT)
Karl D’Souza (10/12/2009 12:30 PM EDT)
Mark Perkins (10/12/2009 12:43 PM EDT)
Keith Wilcock (10/12/2009 01:21 PM EDT)
Michael Quist (10/12/2009 02:14 PM EDT)
Harold Gutch (10/12/2009 03:42 PM EDT)
Satish Vedantam
(10/12/2009 06:46 PM EDT)
Armin Stranjak (10/12/2009 08:26 PM EDT)
Ranjit Eswaran (10/13/2009 03:50 AM EDT)
Aravindakrishnan V. (10/13/2009 04:18 AM EDT)
Radu Borza (10/13/2009 07:45 AM EDT)
Vicente Rubiella Amorós (10/13/2009 08:59 AM EDT)
Basavaraj Kanthi
(10/13/2009 12:01 PM EDT)
Krunoslav Kovac (10/13/2009 01:04 PM EDT)
Emilio Pierro (10/13/2009 02:19 PM EDT)
Mark Pilloff (10/13/2009 07:29 PM EDT)
Shalini Goel (10/14/2009 02:19 AM EDT)
Bobby Brennan (10/14/2009 03:06 AM EDT)
Amos Guler (10/14/2009 04:31 AM EDT)
Fabio Filatrella (10/14/2009 04:46 AM EDT)
Adriana Clerici (10/14/2009 12:34 PM EDT)
Boian Popunkiov (10/14/2009 03:15 PM EDT)
Joshua Lewis (10/14/2009 03:42 PM EDT)
David Banyas (10/14/2009 06:41 PM EDT)
Dave Dodson (10/14/2009 06:51 PM EDT)
Nicholls State Univ. (10/14/2009 09:10 PM EDT)
Josh Kerr (10/14/2009 09:27 PM EDT)
Doug Tonder (10/14/2009 09:30 PM EDT)
Haritha Mathsyaraja (10/15/2009 12:56 AM EDT)
Somesh Kumar (10/15/2009 01:47 AM EDT)
Kaverappa O T (10/15/2009 07:09 AM EDT)
Andrew Buchanan
(10/15/2009 11:41 AM EDT)
Daniel Chong Jyh Tar (10/15/2009 02:10 PM EDT)
Dheeraj Kumar (10/15/2009 05:40 PM EDT)
Mihnea Stoenescu (10/16/2009 04:01 AM EDT)
Ganesh Pagade (10/16/2009 09:40 AM EDT)
Joachim Ripken (10/16/2009 10:12 AM EDT)
Keith Power
(10/16/2009 11:32 AM EDT)
Alexandru Nicau (10/16/2009 11:38 AM EDT)
Kang Seonghoon (10/16/2009 12:01 PM EDT)
Aliaksei Sanko
(10/17/2009 08:33 AM EDT)
Arran Fernandez (10/17/2009 07:27 PM EDT)
Sevag Papazian (10/18/2009 07:06 PM EDT)
Roger (10/18/2009 08:50 PM EDT)
Yin Jintao (10/19/2009 05:38 AM EDT)
Luv Bhatt (10/19/2009 02:17 PM EDT)
Michael Cho & Erdem Varol (10/19/2009 09:12 PM EDT)
Anu Chakravarty (10/19/2009 10:44 PM EDT)
Achava Nakhash (10/19/2009 11:50 PM EDT)
Reinder Verlinde (10/20/2009 04:19 AM EDT)
Amit Chattopadhyay (10/20/2009 04:45 AM EDT)
Ian Barnard (10/20/2009 06:02 AM EDT)
Mauro Lattuada (10/20/2009 11:07 AM EDT)
Aleksandar Damnjanovic
(10/21/2009 12:21 AM EDT)
Romila Pradhan (10/21/2009 05:13 AM EDT)
César Escusa (10/21/2009 10:21 AM EDT)
Meredith Watts (10/21/2009 10:56 AM EDT)
Simone Podico (10/21/2009 11:44 AM EDT)
Kiran Bhogadi (10/21/2009 10:27 PM EDT)
Brendt Hess (10/22/2009 05:48 AM EDT)
Steven Langerwerf (10/22/2009 07:00 AM EDT)
Ionut Poclitaru (10/22/2009 08:40 AM EDT)
Robert Michael
(10/22/2009 03:26 PM EDT)
Gary M. Gerken (10/22/2009 10:47 PM EDT)
Raj Vaidhyanathan (10/23/2009 02:07 AM EDT)
Bernardino Romera Paredes (10/23/2009 08:37 AM EDT)
Guillermo Indalecio (10/23/2009 10:19 AM EDT)
Kalyan Chakravarthy Gudimella
(10/23/2009 01:27 PM EDT)
Ilya Khivrich (10/23/2009 04:22 PM EDT)
Ashutosh Mahajan (10/24/2009 04:47 PM EDT)
Roni Forte (10/25/2009 05:27 PM EDT)
Mahesha In (10/25/2009 05:43 PM EDT)
Sean Lolmaugh (10/26/2009 12:27 AM EDT)
Kartikeya Shandilya (10/26/2009 07:21 AM EDT)
Udit Kapoor (10/26/2009 07:24 AM EDT)
Luke Pebody (10/26/2009 09:20 AM EDT)
Thomas Rohr (10/26/2009 11:12 AM EDT)
Milan Jovanov
(10/26/2009 12:33 PM EDT)
Jonathan McCue (10/26/2009 08:21 PM EDT)
Morgan Sherman (10/27/2009 03:49 AM EDT)
Jack Torres
(10/27/2009 02:24 PM EDT)
Jason L. (10/27/2009 03:42 PM EDT)
Brydon Eastman (10/27/2009 03:48 PM EDT)
Ramkumar Balaraman (10/27/2009 04:52 PM EDT)
Robert Pond (10/27/2009 06:59 PM EDT)
Jesse Benck (10/27/2009 08:56 PM EDT)
Pratik Poddar (10/28/2009 04:38 AM EDT)
Roland Parenteau (10/28/2009 06:12 AM EDT)
Dan Peleg (10/28/2009 08:08 AM EDT)
Carlos Henrique Cano (10/28/2009 09:13 AM EDT)
Yungu Zhu (10/28/2009 09:49 AM EDT)
Chris Shannon
(10/28/2009 08:39 PM EDT)
Nicholas Goken (10/28/2009 09:32 PM EDT)
Bernardo Recamán (10/29/2009 12:42 AM EDT)
Rickard Björklund (10/29/2009 11:22 AM EDT)
Benedikt Engels (10/29/2009 12:10 PM EDT)
Mocanu Calin (10/29/2009 04:36 PM EDT)
Jesse Kolman (10/29/2009 04:44 PM EDT)
Charles Tam (10/29/2009 05:20 PM EDT)
Mayank Singhal (10/30/2009 03:00 AM EDT)
Cristina Popdan (10/30/2009 06:49 AM EDT)
Charles Kingsmill (10/31/2009 01:00 PM EDT)
Scott Smith (10/31/2009 11:37 PM EDT)
James Carter (11/01/2009 10:37 AM EDT)
Geert Jan Ruiter (11/02/2009 03:51 PM EDT)
Maithili Kekre (11/02/2009 02:47 PM EDT)


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