Chromatic symmetric functions via the group algebra of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi>S</mml:mi> <mml:mi>n</mml:mi> </mml:msub></mml:math>

نویسندگان

چکیده

We prove some Schur positivity results for the chromatic symmetric function X G of a (hyper)graph G, using connections to group algebra group. The first such connection works (hyper)forests F: we describe coefficients F in terms eigenvalues product Hermitian idempotents algebra, one factor each edge (a more general formula similar shape holds all chordal graphs). Our main application this technique is conjecture Taylor on certain , which implies formal laws associated various combinatorial generating functions. also introduce pointed G,v rooted graph (G,v). that if and H,w are positive generalized basis Strahov, then wedge sum (G,v) (H,w) positive.

برای دانلود باید عضویت طلایی داشته باشید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Hecke algebra characters and quantum chromatic symmetric functions

We evaluate induced sign characters of Hn(q) at certain elements of Hn(q) and conjecture an interpretation for the resulting polynomials as generating functions for P -tableaux by a certain statistic. Our conjecture relates the quantum chromatic symmetric functions of Shareshian and Wachs to Hn(q) characters. Résumé. Nous évaluons les caractères de signe induits de Hn(q) à certains éléments de ...

متن کامل

Chromatic classical symmetric functions

In this note we classify when a skew Schur function is a positive linear combination of power sum symmetric functions. We then use this to determine precisely when any scalar multiple of a skew Schur function is the chromatic symmetric function of some graph. As a consequence we prove that of the classical bases for symmetric functions only certain scalar multiples of the elementary symmetric f...

متن کامل

Chromatic Symmetric Functions of Hypertrees

The chromatic symmetric function XH of a hypergraph H is the sum of all monomials corresponding to proper colorings of H. When H is an ordinary graph, it is known that XH is positive in the fundamental quasisymmetric functions FS , but this is not the case for general hypergraphs. We exhibit a class of hypergraphs H — hypertrees with prime-sized edges — for which XH is F -positive, and give an ...

متن کامل

Chromatic Bases for Symmetric Functions

In this note we obtain numerous new bases for the algebra of symmetric functions whose generators are chromatic symmetric functions. More precisely, if {Gk}k>1 is a set of connected graphs such that Gk has k vertices for each k, then the set of all chromatic symmetric functions {XGk}k>1 generates the algebra of symmetric functions. We also obtain explicit expressions for the generators arising ...

متن کامل

The Peak Algebra of the Symmetric Group

The peak set of a permutation σ is the set {i : σ (i − 1) < σ (i) > σ (i + 1)}. The group algebra of the symmetric group Sn admits a subalgebra in which elements are sums of permutations with a common descent set. In this paper we show the existence of a subalgebra of this descent algebra in which elements are sums of permutations sharing a common peak set. To prove the existence of this peak a...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

ژورنال

عنوان ژورنال: Algebraic combinatorics

سال: 2022

ISSN: ['2589-5486']

DOI: https://doi.org/10.5802/alco.134