The Favorite Equation of the Professor

A mathematics professor lives in a world of numbers. After an injury, his brain retains memories for only eighty minutes; he remembers neither dates, nor names, nor love, nor friendship — nothing but factorials, prime numbers, and equations.
The maid who... takes care of him is far from mathematics, but the Professor reveals to her and her son the secret world of numbers, where simple and understandable quantities are comparable to the scales of the Universe.
Every morning they get to know each other anew. Each of their days is filled with the mundane, mathematics, baseball, and love.
A novel by Yoko Ogawa, one of the most famous contemporary Japanese writers, about memory, what it means to live in the present, and the mysterious equations that can connect people.