Here is a Black Tree sculpt from their remarkably extensive and comprehensive Doctor Who line. This was DW420, Professor Kettlewell, but I've repurposed him as a mathematical genius visiting Miskatonic from Howard University.
I love the hair.
Bonus points if you recognize the equations!
He looks like he cares for his abstruse and rarefied mathematical theorems, his coffee, and jaunty bow ties, and that's about it. The shabby suit and body language really help sell the character. Brainstein here is one of my favorites.