Quick crossword No 340

A nice, satisfying quick solve this. Simple clues, with clear constructions. I think 14a should be (2,3,8) btw. 17a an example of a perfectly written clue. 12a nice too. 15d also. 18d is just about cryptic... but fine. Initially didn't think "everybody" was needed in 19a but given the nature of the dance, I get it now! Enjoyed it a lot - a smooth fill, without anything too tricksy, and nothing I had to look up to check the parsing. Thanks, Goose. Will definitely solve more :-)

This was really enjoyable! My only gripe is describing mathematicians as 3D. One thing they rarely do is add things up. Perhaps bookkeepers or something might be more accurate.