[math-fun] Things my mother never told me

As a companion piece to the well-known(-ish!) 1 + 2 + 3 + ... = -1/12 https://terrytao.wordpress.com/2010/04/10/the-euler-maclaurin-formula-bernou... the guru has recently given us to understand that (loosely speaking) "the number of finite sets is e " https://terrytao.wordpress.com/2017/04/13/counting-objects-up-to-isomorphism... --- should small children be permitted to overhear such seditious material, one wonders? WFL