Spivak's Calculus formalized in Lean 4 – every theorem, every problem

In plain words

This is a Lean 4 formalization of Michael Spivak's Calculus textbook, containing every theorem and problem from all 30 chapters and 9 appendices across both the 3rd and 4th editions. It is designed for mathematics students and formal verification enthusiasts who want to study calculus with machine-checked proofs. The project's main distinguishing feature is its comprehensive coverage—translating an entire classic textbook into a formal proof assistant rather than selecting fragments.

written from the facts on this page · September 2026

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