Found in 1 comment on Hacker News
haZard_OS · 2018-03-24 · Original thread
Others here have offered some great suggestions already, so I will offer one a little off the beaten path:

Foundations of Mathematics https://www.amazon.com/Foundations-Mathematics-Ian-Stewart/d...

This book is meant to help one transition from performing math in an algorithmic manner to generating proofs based on logic and also set theory.

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