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ynacyesterday at 4:30 PM1 replyview on HN

I once saw a man with a notebook and pencil drawing these kinds of diagrams, at the time I saw them as graph theory. I wasn't in an extrovert moment and missed my chance to ask. He seemed to be working recreationally on them. I'm wondering about puzzles that could be easily created using these theories / maths. You, practitioners, any suggestions?


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susamyesterday at 4:50 PM

> I once saw a man with a notebook and pencil drawing these kinds of diagrams, at the time I saw them as graph theory.

I have been engaged in some work on s-arc transitive graphs in algebraic graph theory. You'd be surprised how rarely I have to draw an actual graph. Most of the time my work involves reasoning about group actions, automorphisms, arc-stabilisers, etc.

For anyone curious what this looks like in practice, I have some brief notes here: <https://susam.net/26c.html#algebraic-graph-theory>. They do not cover the specific results on s-arc-transitivity I have been working on but they give a flavour of the area. A large part of graph theory proceeds without ever needing to draw specific graphs.