A few immediately come to mind: 1. Winning Ways for Your Mathematical Plays 2. A Singular Mathematical Promenade, available for free online: https://perso.ens

A few immediately come to mind: 1. Winning Ways for Your Mathematical Plays 2. A Singular Mathematical Promenade, available for free online: https://perso.ens-lyon.fr/ghys/promenade/ https://perso.ens-lyon.fr/ghys/promenade/ There are many other math books I really like - over the years I've collected a long list of reading recommendations: https://notzeb.com/rec.html https://notzeb.com/rec.html (most of them won't fit as answers to this question)