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We present an explicit construction of a Markovian random growth process on integer partitions such that given it visits some level $n$, it passes through any partition $\lambda$ of $n$ with equal probabilities. The construction has…

Probability · Mathematics 2024-10-01 Yuri Yakubovich

The degree of commutativity of a finite group is the probability that two uniformly and randomly chosen elements commute. This notion extends naturally to finitely generated groups $G$: the degree of commutativity $\text{dc}_S(G)$, with…

Group Theory · Mathematics 2023-10-17 Iker de las Heras , Benjamin Klopsch , Andoni Zozaya

We focus on writing closed forms of generating functions for the number of partitions with gap conditions as double sums starting from a combinatorial construction. Some examples of the sets of partitions with gap conditions to be discussed…

Combinatorics · Mathematics 2021-07-28 Ali K. Uncu

Let $S(\infty)$ denote the infinite symmetric group formed by the finitary permutations of the set of natural numbers; this is a countable group. We introduce its virtual group algebra, a completion of the conventional group algebra…

Representation Theory · Mathematics 2025-04-04 Irina Devyatkova , Grigori Olshanski

Many groups possess highly symmetric generating sets that are naturally endowed with an underlying combinatorial structure. Such generating sets can prove to be extremely useful both theoretically in providing new existence proofs for…

Group Theory · Mathematics 2010-04-22 Ben Fairbairn

Let $G$ be 2-generated group. The generating graph $\Gamma(G)$ of $G$ is the graph whose vertices are the elements of $G$ and where two vertices $g$ and $h$ are adjacent if $G = \langle g, h \rangle.$ This definition can be extended to a…

Group Theory · Mathematics 2020-02-18 Andrea Lucchini

In this paper we provide an asymptotic expansion for the number of independent sets in a general class of regular, bipartite graphs satisfying some vertex-expansion properties, extending results of Jenssen and Perkins on the hypercube and…

Combinatorics · Mathematics 2025-03-31 Maurício Collares , Joshua Erde , Anna Geisler , Mihyun Kang

Using methods from Analytic Combinatorics, we study the families of perfect matchings, partitions, chord diagrams, and hyperchord diagrams on a disk with a prescribed number of crossings. For each family, we express the generating function…

Combinatorics · Mathematics 2023-11-14 Vincent Pilaud , Juanjo Rué

We determine, up to the equivalence of first-order interdefinability, all structures which are first-order definable in the random partial order. It turns out that these structures fall into precisely five equivalence classes. We achieve…

In this paper, we study a family of generating functions whose coefficients are polynomials that enumerate partitions in lower order ideals of Young's lattice. Our main result is that this family satisfies a rational recursion and are…

Combinatorics · Mathematics 2021-07-21 Faqruddin Azam , Edward Richmond

The counting of partitions according to their genus is revisited. The case of genus 0 -- non-crossing partitions -- is well known. Our approach relies on two pillars: first a functional equation between generating functions, originally…

Combinatorics · Mathematics 2023-05-04 Jean-Bernard Zuber

We introduce the list colouring extension of classical Ramsey numbers. We investigate when the two Ramsey numbers are equal, and in general, how far apart they can be from each other. We find graph sequences where the two are equal and…

Combinatorics · Mathematics 2020-08-13 N. Alon , M. Bucić , T. Kalvari , E. Kuperwasser , T. Szabó

Defining a family of recurrences, we generalize Comtet's formula for the generating function of the enumeration of indecomposable permutations. Consequently, we generalize Panaitopol's asymptotic expansion for the prime counting function,…

Combinatorics · Mathematics 2024-12-31 Glenn Bruda

In this article, we study connections between representation theory and efficient solutions to the conjugacy problem on finitely generated groups. The main focus is on the conjugacy problem in conjugacy separable groups, where we measure…

Group Theory · Mathematics 2017-09-29 Sean Lawton , Larsen Louder , D. B. McReynolds

In this paper we prove tight bounds on the combinatorial and topological complexity of sets defined in terms of $n$ definable sets belonging to some fixed definable family of sets in an o-minimal structure. This generalizes the…

Combinatorics · Mathematics 2014-02-26 Saugata Basu

We present two uncountable families of finitely generated residually finite groups all having the same profinite completion. One consists of soluble groups, the other of branch groups.

Group Theory · Mathematics 2021-07-30 Nikolay Nikolov , Dan Segal

We study the connectivity of proper power graphs of some family of finite groups including nilpotent groups, groups with a non-trivial partition, and symmetric and alternating groups.

Group Theory · Mathematics 2014-01-28 Alireza Doostabadi , Mohammad Farrokhi Derakhshandeh Ghouchan

Tensor products of ultrafilters have special combinatorial features closely related to Ramsey's Theorem, making them useful tools in applications. Here we first review their fundamental properties and isolate some new ones, including a…

Combinatorics · Mathematics 2025-06-18 Mauro Di Nasso

This paper initiates the study of effective twisted conjugacy separability for finitely generated groups, which measures the complexity of separating distinct twisted conjugacy classes via finite quotients. The focus is on nilpotent groups,…

Group Theory · Mathematics 2018-08-27 Jonas Deré , Mark Pengitore

In this paper the concept of $\mathbb{F}$-functorial of a finite group was introduced. These functorials have many properties of the Fitting subgroup of a soluble group and the generalized Fitting subgroup of a finite group. It was shown…

Group Theory · Mathematics 2021-03-25 Viachaslau I. Murashka , Alexander F. Vasil'ev