Collatz 5N+1 simulator is a pattern with unknown fate constructed by David Bell in December 2017.
It simulates the Collatz 5N+1 algorithm, that is, starting with an integer, and if it is even divide it by 2, otherwise multiply it by 5 and add 1. When this process is iterated a sequence of numbers is generated. When starting with the value of 7, it is currently unknown whether or not the sequence ever forms a cycle; the trajectory can be found at A259193, starting from the 5th term.
The simulator uses sliding block memory and stable technology, the population of which is always below 32000. Depending on the behaviour of the sequence, the pattern may become stable, or become a high-period oscillator, or have a bounding box which grows irregularly.