Left and right arrows to change slides. I think this is a useful skill to know, and I will definitely be using it in the future. Explanations might be incorrect, but they are technically true. This method also works by replacing the natural log (ln) with scratch's built in log (base 10, the default) and replacing the e^ block with 10^, as it functions on the same principle. Sorry about switching between "powers", "exponents" and "indices", I just sort of do this naturally, but I always mean the same thing.
Thanks to the people in the suggestions forum, specifically the post about adding an ((x) root of (y)) operator block, which is where I found this method. I think it was this post where I originally saw this: https://scratch.mit.edu/discuss/topic/233340/?page=2#post-5474109 #tutorials
