Intuitive geometric sequences (and where to find them in OEIS)

Question

Wondering where intuitive "geometric sequences" are in OEIS. By intuitive, I mean things that you can easily describe to non-math people, as opposed to more obscure concepts that require some deeper mathematical intuitions.

Things that are intuitive are:

1. Number of lines/connections you can draw between two points on the circumference of a polygon. For example, on a 5 sided polygon, if you drew a line from every point to every other point, the number of lines it would be.
2. Number of ways you can draw so they are non-overlapping when connecting points on the circumference of a polygon.
3. Maximum number of overlaps when connecting points on a polygon. (Like bridge crossings).
4. Maximum number of surfaces/areas between lines when connecting points on a polygon. (Like bridge crossings).
5. I can't think of any others.

I would like to be able to find these in OEIS to find basically a table like this:

#sides,max#crossings
5,25
6,26 (just making these numbers up)
7,52
...

#sides,#connections
5,100
6,200 (just making these numbers up)
7,300
...

In addition to finding where these are (and perhaps how to look them up) in OEIS, it would be interesting to note in the comments if there are any other intriguing sequences along the lines of these geometric ones, but not necessary for the question :)

I would like to know how to find more geometric sequences in general (in OEIS), but that's probably too broad of a question.

Answer 1

You find these things either by computing the first low-order terms and enter these numbers into the search bar of the OEIS, or you figure out what a concise description is (like polygon or chord) and enter that into the search bar of the OEIS.