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Ponder This

January 2003

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Ponder This Challenge:

This month's question was supplied by Vinayaka Pandit. Earlier citations will be given with the answer.

Find four points in the plane such that the distance between each pair of points is an odd integer, or show that this is impossible. (The points need not have integer coordinates.)

We are interested in your original solutions, not those that you may have seen elsewhere.

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:


Challenge: 01/06/2003 @ 11:00 AM EST
Solution: 02/03/2003 @ 10:00 AM EST
List Updated: 01/06/2003 @ 11:00 AM EST

People who answered correctly:

Wei Liu (01.06.2003@01:53:50PM EST)
Erick Bryce Wong
(01.06.2003@03:01:43PM EST)
Lizhao Zhang
(01.06.2003@02:00:04PM EST)
Vladimir Sedach
(01.07.2003@03:36:33AM EST)
Ignacio Larrosa Ca˝estro
(01.07.2003@07:29:09AM EST)
Nick McGrath
(01.07.2003@03:13:38PM EST)
Michael Swart
(01.07.2003@03:34:18PM EST)
Karl D'Souza
(01.07.2003@04:04:55PM EST)

Michael Brand (01.08.2003@01:49:09PM EST)
Mikhail Korolik (01.08.2003@06:56:00PM EST)
John G. Fletcher (01.08.2003@09:25:26PM EST)
Vitaly Stakhovsky (01.09.2003@03:24:17AM EST)
Michael Malak (01.09.2003@01:58:57PM EST)
Dan Schwarz (01.09.2003@02:18:52PM EST)
Ajay Reddy Mallepally (01.10.2003@05:22:50AM EST)
Chuck Carroll (01.11.2003@12:14:45AM EST)
Christof Schmalenbach (01.11.2003@03:43:04PM EST)
Chu-Wee Lim (01.11.2003@08:59:48PM EST)
Trevor Graffa (01.12.2003@02:51:26PM EST)
Hagen von Eitzen (01.13.2003@04:06:09AM EST)
Sriram Rallabhandi (01.14.2003@12:36:07PM EST)
Amos Guler (01.15.2003@09:55:50AM EST)
Surendar Nanchary (01.15.2003@01:14:45PM EST)
L.T. Pebody (01.16.2003@10:41:29AM EST)
Biju Mohan (01.16.2003@03:48:48PM EST)
Bengu Li (01.20.2003@06:31:29AM EST)
Mohan Rajagopalan (01.20.2003@06:31:29AM EST)
Bob Stewart (01.20.2003@06:36:11AM EST)
Alex Wagner(01.20.2003@03:45:55PM EST)
Ilan Algor (01.21.2003@08:45:56AM EST)
Andreas Knappe (01.23.2003@01:54:44PM EST)
Thomas Zheng (01.23.2003@11:10:00PM EST)
Algirdas Rascius (01.24.2003@04:44:55AM EST)
Brendan Owen(01.25.2003@03:06:50AM EST)
James Buddenhagen (01.26.2003@07:18:32PM EST)
Prithu B Tiwari (01.29.2003@12:21:00AM EST)
Jose Coelho (01.29.2003@05:26:26PM EST)
Maxim G. Smith (01.30.2003@09:11:47AM EST)
Gyozo Nagy (01.31.2003@02:29:00AM EST)
Peter Huggins (01.31.2003@03:41:03AM EST)

Attention: If your name is posted here and you wish it removed please send email to the webmaster.