[StevenXC]

I like the phrasing used by https://houseofgraphs.org/ — while there are an infinite number of mathematical objects in any category, there are only "a few thousand that can be considered really interesting."

[nurettin]

The same with chess and go. There are way too many move order combinations, but only a few thousand interesting ones.

[tromp]

Happy to have authored A094777, Number of legal positions in Go played on an n X n grid (each group must have at least one liberty), [1] and A269417, Number of Go games on n X n board with no repeating position and suicide allowed. [2].

[1] https://oeis.org/A094777

[2] https://oeis.org/A269417