Readings (for fun and knowledge)
https://www.goodreads.com/book/show/584620.What_Is_Mathematics_An_Elementary_Approach_to_Ideas_and_Methods
https://www.goodreads.com/book/show/4158122-elementary-mathematics-from-an-advanced-standpoint
https://www.goodreads.com/book/show/24113.G_del_Escher_Bach
https://www.goodreads.com/book/show/192221.How_to_Solve_It
https://www.goodreads.com/book/show/1137000.Mathematical_Thought_from_Ancient_to_Modern_Times_Volume_1
For CS
https://www.goodreads.com/book/show/112243.Concrete_Mathematics
https://www.goodreads.com/book/show/309767.Linear_Algebra_and_Its_Applications_with_CD_ROM_
https://www.goodreads.com/book/show/245928.Probability_And_Statistics_For_Engineers_And_Scientists
https://www.goodreads.com/book/show/61298.Calculus
https://www.goodreads.com/book/show/148030.Convex_Optimization
https://www.goodreads.com/book/show/1800803.Discrete_Mathematics_and_its_Applications
https://www.goodreads.com/book/show/24072897-deep-learning
Others
https://www.goodreads.com/book/show/34928283-reverse-mathematics