惯性聚合 高效追踪和阅读你感兴趣的博客、新闻、科技资讯
阅读原文 在惯性聚合中打开

推荐订阅源

J
Java Code Geeks
H
Hackread – Cybersecurity News, Data Breaches, AI and More
Blog — PlanetScale
Blog — PlanetScale
G
Google Developers Blog
Microsoft Security Blog
Microsoft Security Blog
freeCodeCamp Programming Tutorials: Python, JavaScript, Git & More
腾讯CDC
让小产品的独立变现更简单 - ezindie.com
让小产品的独立变现更简单 - ezindie.com
Jina AI
Jina AI
雷峰网
雷峰网
T
Tailwind CSS Blog
爱范儿
爱范儿
OSCHINA 社区最新新闻
OSCHINA 社区最新新闻
酷 壳 – CoolShell
酷 壳 – CoolShell
大猫的无限游戏
大猫的无限游戏
月光博客
月光博客
博客园 - 司徒正美
I
InfoQ
Engineering at Meta
Engineering at Meta
Vercel News
Vercel News
小众软件
小众软件
U
Unit 42
Google DeepMind News
Google DeepMind News
D
DataBreaches.Net

math.CO updates on arXiv.org

Complement Submodular Information Measures for Balanced and Robust Data Selection A Proof of a Conjecture on Positive and Negative Square Energies of Unicyclic Graphs Laplacian Spectrum of the Weakly Zero-Divisor Graph of a Finite Commutative Ring An identity for second Eulerian numbers via lattice-point counting $t$-tone edge coloring of graphs Constructing Maximal Bumpless Pipedreams for Double Grothendieck Polynomials Mubayi's Polynomial-Ideal Conjecture and Cover-Ideal Turán Methods Implicit Binarization via Complex Phase Dynamics in Combinatorial Optimization The limits of Schur multipliers in Pólya conversion problems for the $q$-permanent function Universality theorems for generalized splines Framing Triangulations for Arbitrary Integer Flow Polytopes On the Common Generalization of Gentle Algebras and Framed Directed Acyclic Graphs The complexity of frugal digraph homomorphisms Chaotic and periodic behavior of jeu de taquin on infinite Young tableaux Enumerating Pattern Avoiding Parking Functions Incidence toric ideals and three-point functions Unique Winning Opening Move in Three-Row Chomp Strong majority colorings of graphs A Balancing Theorem for Spanning Trees of Rectangular Grid Graphs Spectral radius and edge-disjoint connected factors of graphs New invariants for rank metric codes, with applications to the classification of rank two semifields of order 256 Flexible DP-4-coloring of planar graphs without 4-cycles and intersecting triangles Balanced intersection size distributions in projective planes List Reconstruction Problem with List Size Two Is Dimensionality a Barrier for Retrieval Models? The INIEP: Irreducible and Positive Realizations The number of Pfaffian orientations on punctured polygonally cellulated surfaces Explicit Construction of Polytopes whose Ehrhart Polynomials Realize any Given Sign Pattern Finite-state enumeration of adjacency-constrained 132-avoiding permutations AMDS and quantum AMDS Constacyclic codes of length $4p^ς$ over $\mathbb{F}_{{p}^{m}}$
The homotopy type of the clique complex of the partition ...
Fedor B. Lyudogovskiy · 2026-03-15 · via math.CO updates on arXiv.org

For each positive integer $n$, let $G_n$ be the graph whose vertices are the partitions of $n$, with edges corresponding to elementary transfers of one cell between two parts, followed by reordering. Let $K_n := \mathrm{Cl}(G_n)$ be the clique complex of $G_n$. We prove that $K_n$ is homotopy equivalent to a wedge of $2$-spheres. More precisely, $K_n$ is homotopy equivalent to a wedge of $b_n$ copies of $S^2$, where $b_n = χ(K_n) - 1$. Thus the homotopy type of $K_n$ is completely determined by its Euler characteristic. The proof has three main ingredients. First, we classify all cliques in $G_n$ via two canonical families of simplices, called star-simplices and top-simplices, and use them to build a canonical cover of $K_n$. Second, we pass to the corresponding nerve, construct a second natural cover, and show via the intersection poset of that cover that $K_n$ has the homotopy type of a CW-complex of dimension at most $2$. Third, using an explicit height function on partitions, we prove that $K_n$ is connected and simply connected. It follows that the reduced homology of $K_n$ is concentrated in degree $2$, where its rank is $χ(K_n) - 1$, and therefore $K_n$ has the homotopy type claimed above. We conclude with remarks on Euler characteristics, small examples, and the integer sequences arising from these complexes.