# The Math behind Against the Day (Part 1): How to win at roulette

Yashmeen Halfcourt is a mathematician and one of the major characters in Pynchon’s book “Against the Day”. And she seems to have figured out a way to beat the odds in roulette using prime numbers? “It is thus obvious from the foregoing that..” is a phrase professors love to use for handwaving away tedious explanations…