<?xml version="1.0" encoding="utf-8"?><feed xmlns="http://www.w3.org/2005/Atom" ><generator uri="https://jekyllrb.com/" version="4.4.1">Jekyll</generator><link href="https://bryangingechen.github.io/CombinatorialRigidity/feed.xml" rel="self" type="application/atom+xml" /><link href="https://bryangingechen.github.io/CombinatorialRigidity/" rel="alternate" type="text/html" /><updated>2026-10-29T18:24:16+00:00</updated><id>https://bryangingechen.github.io/CombinatorialRigidity/feed.xml</id><title type="html">Combinatorial Rigidity</title><subtitle>A Lean 4 / mathlib4 formalization of combinatorial rigidity theory, from Laman&apos;s theorem to the molecular conjecture and the pencil realization theorem.</subtitle></feed>