This is not a performance kata. It can be solved without optimisations in <1 second.

Don't forget the spoiler flag.
The solution was submitted in a different version of Node v8 (if you compare to Chrome), where it worked.

Neither can I. Which led me to the conclusion that this solution is incorrect.

Firstly I have tried to build all expressions by hand and simply add them as throught switch, but I quick understand that build expressoins by hand for numbers larger than 11 is quite impossible :) Great kata, it's my first 1 kyu solved kata. For those who here for searching tips: read about DFA

I've created a Haskell translation. I'd appreciate if somebody could review it. It probably needs some work espescially for the tests. Because Text.Regex.TDFA in Haskell seems to be slower and use more memory than other languages, I had to limit the tests to only be up to n=16.

At this moment is resolved

great kata, i spent two months for solving this kata, first ten my attempts has timed out but last are success.

It's related to caching, it's not a kata issue.

Your points should be updated now.

This Kata upon completion while gave correct progression to next rank gave just 2 honor points (as though it is is level 7 or 8). Why is that?

Very original Kata and unexpected simple strategy found in the description link.

This was super fun, thank you. I studied Formal Languages & Automata theory at C.S., but turning that knowledge into a working algorithm took me a while.
I guess I could refine my solution to produce shorter expressions, but I'll leave it at that for now.

Please review and approve my C translation