
Almost all Collatz orbits attain almost bounded values - weinzierl
https://terrytao.wordpress.com/2019/09/10/almost-all-collatz-orbits-attain-almost-bounded-values/
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jedharris
Those who are upvoting: Why is this interesting / important?

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mgraczyk
The Collatz Conjecture, which the paper described in the blog works toward
proving, is taught in introductory computer science and discrete math courses.
Many people on this site who have gone through a university CS program will
have heard of this problem and its notorious difficulty, so progress would be
familiar and potentially exciting.

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paulddraper
It's a particularly good example of memoization: both simple and without a
suitable DP solution.

    
    
       int collatz(int n) {
         return n == 1 ? 0 : 1 + collatz(n % 2 ? 3 * n + 1 : n / 2)
       }

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tempodox
Is there any special significance to the Collatz function, besides the
sportive aspect of the Collatz conjecture being difficult to prove?

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manifestsilence
I'm not a mathematician, but I'd say that it's one of the simplest and most
elegant instances of its kind, and that in general we don't seem to have good
ways of dealing with iterative processes that can both lengthen and shorten
(or increase and decrease) the size of the output in relation to the input. A
generalization of the proof of this might be quite illuminating for a lot of
hard problems in number or complexity theory.

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adg29
A recent “Full stack engineering” interview duo presented me with a prompt
related to a bounded version of the Collatz conjecture.

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imglorp
Proving something, or coding something?

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adg29
Coding, bounded to 1M. ‘Twas the first time I heard of Collatz. This article
is the second in as many weeks

