This is the comment I gave on Meta: "What exactly is a "research mailing list"? Most lists I know contain mostly announces of conferences, books, open positions; would those qualify? Or do you expect members to ask and answer questions with mathematical content, like here on MO?". But I doubt OP will reply, since they are inactive from 2017.

You repeated a couple of times that you feel this is "research-adjacent" and "of interest to research mathematicians", but you did not provide arguments why. Is there a research angle that is not apparent to me, or is your argument that this should be interesting to research mathematicians just because many research mathematicians also have to teach calculus?

I don't see a research mathematics angle in this question; this looks like undergraduate teaching material.

got it, thanks!

Thanks! That seems on point, but tricky to process for me. One question for now: in the figure on page 7 (resp. 57), it seems that the edges point not only away from $j$, but also towards $i$. Is that an additional condition that needs to be verified?

@JankoBracic This looks like a good answer, I suggest you post it as one.

@DavidRoberts I am the one that added gm.general-mathematics to the original 2 vs. 3 question; I assume the tags were reused here as they are in the other question. I thought the guideline is that every question should have a "top-level" Arxiv tag, and gm looked like the only fitting one. Feel free to remove it if you disagree! And if this tag has a special meaning, I suggest making it clear in its tag wiki.

See this thread on Computational Science for many examples.

@NathanielJohnston Thanks, the suggestion was spot-on. I have filled in the blanks in a CW answer, but if you wish to write your own answer I will be happy to accept it.