I'd have to disagree - the math is important, and lays a foundation for functional/declarative programming. One major lesson of Chapter 1 (where the math is most evident) is conceptually tying math (and its notations) with functional, declarative programming. Math still shows up in Chapters 2 (e.g. generic operations, polar vs. rectangular coordinate system math) and 3 (streams). It can't be skipped over without missing a lot of lessons.