Fair point Voile, I didn't think about how small the sequence is, just thought it would add an interesting extra layer of complexity to the existing upside-down integers kata. Oh well, live and learn.

I love the idea of this kata, but I really felt your README let it down. It wasn't at all clear what methods the ORM is expected to make available.

The fact that records should only be saved to the 'database' when an explicit save message is sent, and not on instantiation, is pretty counter-intuitive.

Nice. Definitely an improvement in my opinion. Also, apologies for flagging this as an 'ISSUE', I didn't mean to!

This may well just be my less-than-stellar grasp of mathematics but I, personally, found the instructions a little confusing. Just FYI.

Ok, I've added some random tests. Thanks again for the advice :)

Thanks for the feedback! Could you please point me in the direction of the existing kata that deals with this? I couldn't find any when I looked.

I'm British. Haha.

Don't get me wrong Unihedron, I think it's a beautiful solution, I just wish I'd thought of it myself!

Smart arse