I don't think anyone is really sure what Pottermore is about.
You're so pretty today :)
My parents do.
Unless they steal that obsession from you and call it their own. Then you just want to punch them in the face.
For those that don't get it;
(√-1) is an imaginary number denoted by 'i'
(23) is 2 x 2 x 2, which is '8'
Σ is the greek letter capital Sigma, used as short hand for 'sum'
(inverse cos(-1)) = π, or 'pi'.
(i)(8)(sum)(pi), and it was good.
Because sometimes, you have to spoil the joke for people to get it.