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Ponder This

February 2013

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Ponder This Challenge:

James Tanton tweeted ( https://twitter.com/jamestanton/status/293127359291330561) that "16 and 9 are each square numbers, and putting them together, 169, gives another square" and he then asked for other examples.

Our challenge this month is to find integers x, y, and z such that concatenating x^2 and y^2 gives z^2, and that z has at least four consecutive nines.

Update 2/6: the challenge stating that x,y and z should be non-zero.


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: 02/01/2013 @ 01:00 PM EST
Solution: 03/01/2013 @ 01:00 PM EST
List Updated: 02/01/2013 @ 01:00 PM EST

People who answered correctly:

Joseph DeVincentis (02/01/2013 01:44 PM EDT)
Adel El-Atawy (02/01/2013 02:04 PM EDT)
Dennis Langdeau (02/01/2013 03:17 PM EDT)
Kevin Bauer (02/01/2013 03:33 PM EDT)
Donald Dodson (02/01/2013 03:35 PM EDT)
Martin Husar (02/01/2013 03:36 PM EDT)
Sergey Grishaev (02/01/2013 03:59 PM EDT)
Peter Gerritson (02/01/2013 04:07 PM EDT)
Markus von Rimscha (02/01/2013 04:07 PM EDT)
Vladimir Sedach (02/01/2013 04:27 PM EDT)
Stéphane Higueret (02/01/2013 05:20 PM EDT)
Todd Will (02/01/2013 05:33 PM EDT)
Bartosz Budzanowski (02/01/2013 05:51 PM EDT)
Rudy Cortembert (02/01/2013 05:54 PM EDT)
Deane Stewart (02/01/2013 05:59 PM EDT)
Anders Kaseorg (02/01/2013 06:36 PM EDT)
Sunil Srivastava (02/01/2013 07:21 PM EDT)
Deron Stewart (02/01/2013 11:32 PM EDT)
Radu-Alexandru Todor (02/01/2013 10:51 PM EDT)
Andrey Stepin (02/02/2013 12:47 AM EDT)
Alex Wagner (02/02/2013 02:43 AM EDT)
Oleg Zlydenko (02/02/2013 04:35 AM EDT)
Leandro Araújo
(02/02/2013 07:15 AM EDT)
Tony Harrison (02/02/2013 09:07 AM EDT)
Mark Stuckel (02/02/2013 10:35 AM EDT)
Hakan Summakoglu (02/02/2013 11:30 AM EDT)
Jesus Sanz (02/02/2013 12:48 PM EDT)
Klaus Müller (02/02/2013 12:57 PM EDT)
Øyvind Grotmol (02/02/2013 02:21 PM EDT)
Andreas Stiller (02/02/2013 06:13 PM EDT)
Florian Fischer (02/02/2013 06:21 PM EDT)
Tao Cheng (02/02/2013 06:29 PM EDT)
Dan Dima (02/03/2013 02:56 AM EDT)
Roberto Tauraso (02/03/2013 03:36 AM EDT)
Philippe Fondanaiche (02/03/2013 08:32 AM EDT)
Harald Bögeholz (02/03/2013 10:51 AM EDT)
Deepak Bal (02/03/2013 11:16 AM EDT)
Paul McKenney (02/03/2013 02:29 PM EDT)
Daniel Bitin (02/03/2013 02:33 PM EDT)
Antoine Comeau (02/03/2013 04:32 PM EDT)
Dan Ignatoff (02/03/2013 06:51 PM EDT)
Michael Liepelt (02/04/2013 03:23 AM EDT)
Peter Holdsworth (02/04/2013 04:40 AM EDT)
Luke Pebody (02/04/2013 05:36 AM EDT)
Chuck Carroll (02/04/2013 10:24 AM EDT)
Arun C Ramachandran (02/04/2013 11:58 AM EDT)
Frederik Kaster (02/04/2013 12:15 PM EDT)
William Gunther (02/04/2013 12:27 PM EDT)
Puvichakravarthy Ramachandran (02/04/2013 01:31 PM EDT)
Seth Troisi (02/04/2013 02:21 PM EDT)
Hugo Pfoertner (02/04/2013 05:24 PM EDT)
Christian Pape (02/04/2013 07:22 PM EDT)
José Eduardo Gaboardi de Carvalho (02/04/2013 08:28 PM EDT)
Kurt Hectic (02/05/2013 09:35 AM EDT)
Armin Krauss (02/05/2013 09:50 AM EDT)
David Greer (02/05/2013 10:21 AM EDT)
Duane Bailey (02/05/2013 12:38 PM EDT)
Duane Ryan (02/05/2013 12:43 PM EDT)
Duane R. Bailey (02/05/2013 12:02 PM EDT)
Shirish Chinchalkar (02/05/2013 06:56 PM EDT)
Ignat Soroko (02/05/2013 09:37 PM EDT)
Liubing Yu (02/05/2013 10:11 PM EDT)
Javier Rodriguez (02/06/2013 03:16 AM EDT)
Ranjit Eswaran (02/06/2013 05:52 AM EDT)
Luis Mendes (02/06/2013 07:02 AM EDT)
Arthur Vause (02/06/2013 08:39 AM EDT)
Dave English (02/06/2013 10:30 AM EDT)
Karan P Dhadge (02/06/2013 11:30 AM EDT)
Jason Crease (02/06/2013 01:16 PM EDT)
Richard Gosiorovsky (02/06/2013 02:59 PM EDT)
Jeff Irwin (02/06/2013 04:07 PM EDT)
Joe Clark (02/07/2013 01:57 AM EDT)
Philippe Laborie (02/07/2013 01:57 AM EDT)
Kapil Agrawal (02/07/2013 03:32 AM EDT)
Vivek Ranjan Nema (02/07/2013 03:37 AM EDT)
Mahendra Kariya (02/07/2013 06:36 AM EDT)
Thomas Egense (02/07/2013 06:38 AM EDT)
János Kramár (02/07/2013 06:42 AM EDT)
Sandeep Navada (02/07/2013 08:38 AM EDT)
Greg Janée (02/07/2013 09:51 AM EDT)
Luis Ramada Pereira (02/07/2013 11:05 AM EDT)
J. Eric Ivancich (02/07/2013 02:10 PM EDT)
Gregory Fritz (02/07/2013 02:18 PM EDT)
Michael Slifker (02/07/2013 02:33 PM EDT)
Jerry Kearns (02/07/2013 02:35 PM EDT)
Tilmann Steinberg (02/07/2013 03:18 PM EDT)
Peter gabrovsek (02/07/2013 03:49 PM EDT)
Mathias Schenker (02/07/2013 04:21 PM EDT)
Stephan Weber (02/07/2013 04:57 PM EDT)
Jianhua Cheng (02/07/2013 07:39 PM EDT)
Joaquim Neves Carrapa (02/07/2013 07:52 PM EDT)
Matej Kollar (02/08/2013 08:00 AM EDT)
Sevag Papazian (02/08/2013 09:38 AM EDT)
Fabien Petronelli (02/08/2013 09:53 AM EDT)
Chris Shannon (02/08/2013 07:18 PM EDT)
Mark Pervovskiy (02/09/2013 11:31 AM EDT)
Stephan Weber (02/09/2013 01:10 PM EDT)
Andrei Zaharescu (02/10/2013 08:21 AM EDT)
Luis Manuel Frutos (02/10/2013 03:40 PM EDT)
Priyanka Gagneja Dhingra (02/10/2013 11:02 PM EDT)
Olivier Mercier (02/11/2013 02:24 PM EDT)
David Vainapel (02/11/2013 07:13 AM EDT)
Siva Dirisala (02/12/2013 02:13 PM EDT)
Rob McColl (02/12/2013 05:32 PM EDT)
David Dodson (02/12/2013 05:55 PM EDT)
Victor Chang (02/12/2013 10:41 PM EDT)
Thomas Rohr (02/13/2013 05:11 AM EDT)
Paul Mandell (02/14/2013 07:28 AM EDT)
Vincent Lejeune (02/14/2013 10:29 AM EDT)
Ante Kovacic (02/14/2013 06:57 PM EDT)
Ryan Rechkemmer (02/14/2013 07:08 PM EDT)
Ian Barnard (02/15/2013 04:08 AM EDT)
Jan Fricke (02/15/2013 05:28 AM EDT)
Peter Park (02/15/2013 06:03 AM EDT)
Kipp Johnson (02/15/2013 09:29 AM EDT)
Adir HaCohen (02/15/2013 10:24 AM EDT)
Lewei Weng (02/16/2013 12:06 AM EDT)
Dylan Rose (02/16/2013 01:27 AM EDT)
Jose Nazario (02/16/2013 01:53 PM EDT)
Adrian Orzepowski (02/17/2013 07:57 AM EDT)
Luis Ramada Pereira (02/17/2013 11:29 AM EDT)
Jochen Klein (02/17/2013 03:32 PM EDT)
Don Ryan (02/17/2013 11:26 PM EDT)
Shouky Dan & Tamir Ganor (02/17/2013 11:47 PM EDT)
Sami Casanova (02/18/2013 08:57 AM EDT)
Rodrigo Viana Rocha (02/18/2013 08:42 PM EDT)
Jens Schönbohm (02/19/2013 06:02 AM EDT)
José Eduardo Gaboardi de Carvalho (02/19/2013 10:25 AM EDT)
Kerry M. Soileau (02/19/2013 08:07 PM EDT)
Shmuel Menachem Spiegel (02/19/2013 11:38 PM EDT)
Minghao (Tommy) Liang (02/20/2013 01:42 PM EDT)
Philip Ward (02/20/2013 02:51 PM EDT)
Raphael Deem (02/20/2013 04:54 PM EDT)
Edgardo Deza (02/20/2013 08:47 PM EDT)
Nyles Heise (02/20/2013 10:35 PM EDT)
Michael Holschbach (02/21/2013 01:13 PM EDT)
Mark Kattenbelt (02/21/2013 03:00 PM EDT)
Max & Nick Nepokroeff (02/22/2013 12:22 AM EDT)
Abhiram R Devesh (02/22/2013 09:47 AM EDT)
Anoop Ghanwani (02/24/2013 04:06 AM EDT)
Albert Stadler (02/24/2013 06:19 AM EDT)
Moritz Pflanzer (02/24/2013 08:21 AM EDT)
Jorge Soares (02/25/2013 05:58 AM EDT)
Aditya Vohra (02/25/2013 03:07 AM EDT)
Jamie Jorgensen & Jason Lee (02/25/2013 08:16 PM EDT)
Tomek Czajka (02/27/2013 05:26 PM EDT)
Benjamin Bachmann (02/27/2013 06:33 PM EDT)
Simon Xu (02/27/2013 07:57 PM EDT)
Nadav Ben-Nun (02/27/2013 08:10 PM EDT)
Dugan Schmid (02/27/2013 10:06 PM EDT)
Donald Dodson (02/28/2013 09:15 AM EDT)
John Flavin (02/28/2013 01:42 PM EDT)
Dugan Schmid & Craig Oppenheim (02/28/2013 02:19 PM EDT)
Benjamin Burch (02/28/2013 05:46 PM EDT)


Attention: If your name is posted here and you wish it removed please send email to the ponder@il.ibm.com.