What's New -  January, 2010

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A Numbrix Puzzle

Solved!

January 17, 2010:  Consider the sequence formed if, starting with any positive integer, we form a sequence where for the sequence ending with N, then next entry is N/2  if N is even and 3N+1 if N is odd.  Starting with 3 for example, the sequence is [3, 10, 5, 16, 8, 4, 2, 1].  The unproven conjecture (the "Collatz" conjecture) is that any such sequence will eventually degenerate to 1.  Here's a beginner's level program, ThreeNPlus1, that evaluates all sequences within a given range and reports the longest sequence found.  

January 12, 2010:   DFF Newsletter #55 was sent yesterday using the latest version of MailList King, a mailing list management program from Xequte Software. The program is written in Delphi and contains all the features needed to simplify newsletter sending such as automatic subscribing/unsubscribing, limiting the sending rate to comply with host server limits, processing undeliverable email responses to clean the list, etc.  The $99 personal edition does everything I need and is recommended if you ever have the need.

A university student recently took on a Java version of the MasterMind game as a school project.  He wrote asking about my "Smarter than you" intelligence level which can be applied when the program is doing the guessing about the secret pattern.  The program has a Verbose mode which was supposed to help debugging and explaining the search steps, but the messages were being cleared after each computer guess.  MasterMind Version 2.1 corrects this and hopefully will help him and others understand the mini-max guessing procedure used at the smartest level.  
   

January 9, 2010:

"Instant Insanity" is a variation of an older cube arrangement puzzle and one of a large family of similar puzzles. In this one, we have four cubes with one of four colors on each face of each cube.  The objective is to stack the cubes so each column of  faces has all four colors.

A viewer recently asked for help in developing a Delphi solver version.  Most of the online literature describes a graph search algorithm which can be applied to find solutions with pencil and paper.  With a faster but dumber computer, it's easiest just to check all 41,472 possible arrangements  looking for  solutions.  Instant Insanity Version 1.0 posted today does just that with a few sample or user defined cube sets. 


January 4, 2010:

 Red wins! 

While playing the "Wii Play" version of the Four-In-A-Row game with a grandson over the holidays, I used my Delphi version of the game to advise me on  moves to make.  I was embarrassed to find that the program's random moves "enhancement" frequently allowed Chris to win by placing 4 adjacent token in his first 4 moves - the initial random moves feature assumed that there would be no winner that soon.  Four In A Row Version 2.2 posted today fixes the problem by limiting initial random moves to 2 or 3 turns. 
   

January 2, 2010:  

Happy New Year!   We'll kick off the new year with a program that I wrote a year or so ago but never got around to posting.  Accordion Solitaire is a simple solitaire card game that is difficult to win; perhaps one win in 100 games.   This version allows user and program play and implements a "sweeper" strategy of play which can increase the odds of winning to perhaps 10%