Looking for a specific research illustration on how LLMs "do maths"

Hey all,

I'm losing my wits over not being able to find an article again that I've seen either on lemmy or reddit, and I figured this community might know.

It was about a research team somehow cracking open an LLM and looking at the way it does calculations, and I remember there was a sort of flowchart in the article, with the LLM grouping interim results into weird-ass categories, like "between 26-ish and 34-ish", and then using a separate process for figuring out the last digit.

I think the article might have been linked in response to a question like why LLMs mess up the last digit of number calculations.

Any of this rings a bell to someone? I've tried searching for it in any way I can phrase the idea, but all I get is a flood of ads and guides about "how to do math in LLMs".