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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 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: 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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