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Subject: "Integer Points on a Circle"     Previous Topic | Next Topic
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Conferences The CTK Exchange Thoughts and Suggestions Topic #36
Reading Topic #36
amphibius jones
guest
Mar-29-08, 00:05 AM (EST)
 
"Integer Points on a Circle"
 
   The page for this interesting problem
https://www.cut-the-knot.org/SimpleGames/IntIter.shtml
seems to contain glaring errors. The statement that the only way to get a sequence of all equal numbers is for the previous sequence to be all even or all odd is definitely false. Simply consider 1212 which yields 1111. The same oversight appears later in the page when it is stated that only nonconstant sequences converge when N is a power of 2. Again, 121212 is a sequence of 6 which clearly converges to zeros (of course this counterexample extends to any even N). In fact, one checks that up to translation, scaling, rotation and reflection, there are exactly three nonzero sequences of length six which converge to zeros. Is there some restriction on the sequences that isn't mentioned (or that I missed)?


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alexbadmin
Charter Member
2213 posts
Mar-30-08, 10:35 AM (EST)
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1. "RE: Integer Points on a Circle"
In response to message #0
 
   You are right and I very much appreciate your pointing out the errors.

Many thanks. Would you mind giving me your real name? I'll be happy to credit you with the observation. You may use my email: alexb@cut-the-knot.com.


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