in mathworld, they say that conway proved "that Collatz-type problems can be formally undecidable."(adsbygoogle = window.adsbygoogle || []).push({});

does it mean that this problem is undecidable?

if yes i dont know why for example in the website of plus.maths.org they still saying it hasnt been proven/disproven.

anyway, i tinkerred around with the original conditions of the problems and instead of when n is even n'=n/2 and when n is odd n'=3*n+1

i decided to switch to when n is even n'=n/2+1 when n is odd n'=2n

this sequence is limited from the original because if you start with 2 you get 2 all the way, but besides this and the number 1 (which gives you a repeating sequence of 1,2,1,2....) they yield also a repeating cycle as the one given by the original problem but instead of 4,2,1 cycle you get a 6,4,3 cycle (yes plus two than the original), im not familiar too much to recursion so im not sure if this is a trivial thing.

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# Collatz problem

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