Peter Nelson, Formalizing matroid theory in a proof assistant
For the past few years, I've been working on formalizing proofs in matroid theory using the Lean proof assistant. This has led me to many interesting and unexpected places. I'll …
For the past few years, I've been working on formalizing proofs in matroid theory using the Lean proof assistant. This has led me to many interesting and unexpected places. I'll …
The 2024 Workshop on (Mostly) Matroids will be held in-person at the Institute for Basic Science (IBS), Daejeon, South Korea, from August 19, 2024 to August 23, 2024. We expect …
Every (finite) matroid consists of a (finite) set called the ground set, and a collection of distinguished subsets called the independent sets. A classic example arises when the ground set …
Website: https://cw2024.combinatorics.kr/ Location Chungbuk National University, Cheongju, Korea. Advisory Committee Committee of Discrete Mathematics, The Korean Mathematical Society (Chair: Sang-il Oum, IBS Discrete Mathematics Group / KAIST) Sponsors IBS Discrete …
In 1980, Burr conjectured that every directed graph with chromatic number $2k-2$ contains any oriented tree of order $k$ as a subdigraph. Burr showed that chromatic number $(k-1)^2$ suffices, which …
An edge-colored graph $H$ is called rainbow if all of its edges are given distinct colors. An edge-colored graph $G$ is then called rainbow $H$-free when no copy of $H$ in …
We prove the following variant of Helly’s classical theorem for Hamming balls with a bounded radius. For $n > t$ and any (finite or infinite) set $X$, if in a …
We say that a 0-1 matrix A contains another such matrix (pattern) P if P can be obtained from a submatrix of A by possibly changing a few 1 entries …
Rödl and Ruciński established Ramsey's theorem for random graphs. In particular, for fixed integers $r$, $\ell\geq 2$ they showed that $n^{-\frac{2}{\ell+1}}$ is a threshold for the Ramsey property that every …
In general, random walks on fractal graphs are expected to exhibit anomalous behaviors, for example heat kernel is significantly different from that in the case of lattices. Alexander and Orbach …