<h2>Overview</h2>
<p>Lean 3's mathlib is a library for the Lean theorem prover that is no longer actively maintained. It is recommended to use mathlib4 for Lean 4 instead.</p>
<h2>Features</h2>
<ul>
<li><strong>Lean theorem prover</strong>: Mathlib provides a library of formalized mathematics that can be used with the Lean theorem prover.</li>
<li><strong>Extensive coverage</strong>: Mathlib 3 contains a wide range of formalized mathematics, including algebra, calculus, number theory, and more.</li>
<li><strong>Community-driven</strong>: Mathlib is a collaborative project, with contributions from a community of mathematicians and computer scientists.</li>
</ul>
<h2>Summary</h2>
<p>Mathlib 3 is a library for the Lean theorem prover that is no longer actively maintained. It is recommended to switch to mathlib4 for Lean 4, as it is the actively maintained version. Mathlib provides an extensive library of formalized mathematics and is a community-driven project. To install mathlib4, follow the provided installation guide.</p>


Leanprover Community

Mathlib3