Ponder This

June 2005

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Ponder This Challenge:

Puzzle for June:

This puzzle is based on a suggestion by Aditya K Prasad,
(Further attribution will be given with the solution.)

Consider a string S of N symbols, selected from the set {A,B}.
In any consecutive substring of S,
the number of A's differs from the number of B's by at most 3.
How many such strings S are there (as a function of N, in closed form)?

We are not accepting solutions for this month.

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Challenge: 06/01/2005 @ 08:30 AM EST
Solution: 07/01/2005 @ 08:30 AM EST
List Updated: 06/01/2005 @ 08:30 AM EST

(No "correct responses" list this month)

We are not accepting solutions for this month.

Raicho Tchalkov (06.01.2005 @12:56:28 PM EDT)
Eugene Vasilchenko (06.01.2005 @02:51:21 PM EDT)
David Friedman (06.01.2005 @03:36:32 PM EDT)
Vlad Gotlib (06.01.2005 @10:01:20 PM EDT)
Huicheng Guo (06.01.2005 @11:47:38 PM EDT)
Max Alekseyev (06.02.2005 @02:57:58 AM EDT)
Luke Pebody (06.02.2005 @05:57:06 PM EDT)
David McQuillan (06.02.2005 @07:51:25 AM EDT)
Brian J. (06.02.2005 @10:00:17 AM EDT)
Bart De Vylder (06.02.2005 @10:37:36 AM EDT)
Matteo Slanina (06.02.2005 @03:05:55 PM EDT)
Steven Noble (06.02.2005 @03:29:22 PM EDT)
Tomas G. Rokicki (06.02.2005 @05:27:33 PM EDT)
Patrick J. LoPresti (06.02.2005 @06:28:14 PM EDT)
Jan Kuipers (06.02.2005 @09:33:03 PM EDT)
Mark Pilloff (06.02.2005 @09:37:24 PM EDT)
Dan Dima (06.02.2005 @07:40:20 PM EDT)
Machine (06.03.2005 @02:07:00 AM EDT)
Chang-SeoPark (06.03.2005 @06:11:24 AM EDT)
Robert Benea (06.03.2005 @06:26:41 AM EDT)
Daniel Bitin (06.03.2005 @12:50:05 PM EDT)
Yong Liu (06.03.2005 @02:57:00 PM EDT)
Abishek K (06.04.2005 @12:24:18 AM EDT)
Kennedy (06.04.2005 @12:57:22 AM EDT)
Alvaro Martinez Echevarria (06.04.2005 @10:02:12 AM EDT)
Vladimir Sedach (06.04.2005 @11:27:31 AM EDT)
Todd G. Will (06.04.2005 @02:11:43 PM EDT)
Clive Tong (06.04.2005 @04:13:09 PM EDT)
Franco Bassi (06.05.2005 @04:39:25 PM EDT)
Vijay Tennety (06.06.2005 @04:45:53 AM EDT)
Roberto Tauraso (06.06.2005 @06:28:05 AM EDT)
John Hart (06.06.2005 @12:45:53 PM EDT)
John Tromp (06.06.2005 @01:16:42 PM EDT)
Dharmadeep Muppalla (06.07.2005 @02:22:43 AM EDT)
Dinesh Layek (06.07.2005 @12:52:02 PM EDT)
William C. Hasenplaugh (06.07.2005 @06:13:08 PM EDT)
Brad Austin (06.08.2005 @01:01:58 AM EDT)
Radu Grigore (06.08.2005 @01:41:08 AM EDT)
Udo Klein (06.08.2005 @02:26:16 AM EDT)
Patricio Alva (06.08.2005 @11:34:50 AM EDT)
Guy Srinivisan (06.08.2005 @04:52:11 PM EDT)
Andre Rzym (06.08.2005 @05:30:29 PM EDT)
Hao Wu (06.08.2005 @09:51:23 PM EDT)
Leonardo Liang (06.09.2005 @05:38:02 AM EDT)
Mike Fee (06.09.2005 @07:09:25 AM EDT)
Se Kwon Kim (06.09.2005 @10:44:35 PM EDT)
Balakrishnan V (06.10.2005 @01:56:11 AM EDT)
Vineet Dwivedi (06.10.2005 @02:32:00 AM EDT)
Chuck Carroll (06.10.2005 @03:53:57 AM EDT)
Atilla Eryilmaz and Irem Koprulu (06.10.2005 @08:53:41 PM EDT)
John Hubenschmidt (06.10.2005 @10:48:03 AM EDT)
Mayank Bathiya (06.10.2005 @10:48:08 AM EDT)
Emilio Schiavi (06.10.2005 @06:55:53 PM EDT)
Youssef Mohammed (06.13.2005 @01:53:44 AM EDT)
Jose H. Nieto (06.13.2005 @07:55:21 AM EDT)
Shirish Altekar (06.14.2005 @06:01:11 PM EDT)
Daniel Chong Jyh Tar (06.15.2005 @07:31:06 AM EDT)
Dave Biggar (06.16.2005 @09:00:04 AM EDT)
Srikanth S.M. (06.16.2005 @09:37:46 AM EDT)
IQSTAR (06.17.2005 @08:03:36 AM EDT)
Divyesh Dixit (06.17.2005 @01:57:48 PM EDT)
Peter Mattsson (06.17.2005 @06:29:07 PM EDT)
Wolf Mosle (06.20.2005 @11:40:17 PM EDT)

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