When you toss “2241 + 19873 =” into an applet that shows you the default tokenization scheme GPT-3 uses, you get this:
(224)(1)( +)( 198)(73)( =)
I’ve heard it remarked before that, while tokenization is obviously an unavoidable part of a model with an architecture like GPT, this is a very silly way of tokenizing number strings for the purposes of learning or doing arithmetic. Indeed, I think a lot of GPT-3’s puzzling edge-case performance can be ascribed to weird and unhelpful tokenizations. Just imagine if you were forced to learn arithmetic with a brain that automatically categorized “224” as a sort of distinct object, or, for that matter, breaking down 19873 as ( 198)(73) rather than (19873) or (1)(9)(8)(7)(3) or anything practically useful.
The thing is that we can, in a sense, learn better “tokenizations”, in the sense that a 4 year old learning to read sees letters, while a 40 year old reading a novel “sees” whole words or even groups of words. The GPT architecture can’t change its tokenization scheme.