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Related papers: Odd length: odd diagrams and descent classes

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It is known that, when $n$ is even, the number of permutations of $\{1,2,\dots,n\}$ all of whose cycles have odd length equals the number of those all of whose cycles have even length. Adin, Heged\H{u}s and Roichman recently found a…

Combinatorics · Mathematics 2025-04-08 Sergi Elizalde

A grid class consists of permutations whose pictorial depiction can be partitioned into increasing and decreasing parts as determined by a given matrix. In this paper, we introduce a method for enumerating cyclic permutations in vector grid…

Combinatorics · Mathematics 2018-08-27 Kassie Archer , L. -K. Lauderdale

We give a unified description of twisted forms of classical reductive groups schemes. Such group schemes are constructed from algebraic objects of finite rank, excluding some exceptions of small rank. These objects, augmented odd form…

Group Theory · Mathematics 2026-05-08 Egor Voronetsky

A special type of conjugacy classes in symmetric groups is studied and used to answer a question about odd-degree irreducible characters

Representation Theory · Mathematics 2008-12-31 Jorn B. Olsson

We study aspects of the enumeration of permutation classes, sets of permutations closed downwards under the subpermutation order. First, we consider monotone grid classes of permutations. We present procedures for calculating the generating…

Combinatorics · Mathematics 2015-06-23 David Bevan

We show that the universal odd Chern form, defined on the stable unitary group $U$, extends to the loop group $LU$ in a way that is closed with respect to an equivariant-type differential. This provides an odd analogue to the Bismut-Chern…

Algebraic Topology · Mathematics 2013-11-27 Scott O. Wilson

Noting that cycle diagrams of permutations visually resemble grid diagrams used to depict knots and links in topology, we consider the knot (or link) obtained from the cycle diagram of a permutation. We show that the permutations which…

Combinatorics · Mathematics 2020-07-10 Christopher R. Cornwell , Nathan McNew

We consider a large family of equivalence relations on permutations in Sn that generalise those discovered by Knuth in his study of the Robinson-Schensted correspondence. In our most general setting, two permutations are equivalent if one…

Combinatorics · Mathematics 2011-11-17 Steven Linton , James Propp , Tom Roby , Julian West

In this paper, we deal with reversing and extended symmetries of shifts generated by bijective substitutions. We provide equivalent conditions for a permutation on the alphabet to generate a reversing/extended symmetry, and algorithms how…

Dynamical Systems · Mathematics 2026-03-02 Álvaro Bustos , Daniel Luz , Neil Mañibo

Involution words are variations of reduced words for involutions in Coxeter groups, first studied under the name of "admissible sequences" by Richardson and Springer. They are maximal chains in Richardson and Springer's weak order on…

Combinatorics · Mathematics 2018-08-07 Zachary Hamaker , Eric Marberg , Brendan Pawlowski

An odd prime labeling is a variation of a prime labeling in which the vertices of a graph of order~$n$ are labeled with the distinct odd integers $1$ to $2n-1$ so that the labels of adjacent vertices are relatively prime. This paper…

Combinatorics · Mathematics 2022-08-19 Holly Carter , N. Bradley Fox

We introduce and characterise grid classes, which are natural generalisations of other well-studied permutation classes. This characterisation allows us to give a new, short proof of the Fibonacci dichotomy: the number of permutations of…

Combinatorics · Mathematics 2007-05-23 Sophie Huczynska , Vincent Vatter

In this article we consider square permutations, a natural subclass of permutations defined in terms of geometric conditions, that can also be described in terms of pattern avoiding permutations, and convex permutoninoes, a related subclass…

Combinatorics · Mathematics 2023-06-22 Enrica Duchi

We investigate gauge anomalies in the context of orbifold conformal field theories. Such anomalies manifest as failures of modular invariance in the constituents of the orbifold partition function. We review how this irregularity is…

High Energy Physics - Theory · Physics 2021-10-13 Daniel Robbins , Eric Sharpe , Thomas Vandermeulen

Inspired by a width invariant on permutations defined by Guillemot and Marx, Bonnet, Kim, Thomass\'e, and Watrigant introduced the twin-width of graphs, which is a parameter describing its structural complexity. This invariant has been…

Logic in Computer Science · Computer Science 2024-08-07 Édouard Bonnet , Jaroslav Nešetřil , Patrice Ossona de Mendez , Sebastian Siebertz , Stéphan Thomassé

We compute the transgressed forms of some modularly invariant characteristic forms,which are related to the twisted elliptic genera. We study the modularity properties of these secondary characteristic forms and relations among them. We…

Differential Geometry · Mathematics 2010-03-04 Yong Wang

The circular descent of a permutation $\sigma$ is a set $\{\sigma(i)\mid \sigma(i)>\sigma(i+1)\}$. In this paper, we focus on the enumerations of permutations by the circular descent set. Let $cdes_n(S)$ be the number of permutations of…

Combinatorics · Mathematics 2008-06-05 Hungyung Chang , Jun Ma , Yeong-Nan Yeh

The classes of odd graphs $O_n$ and middle levels graphs $B_n$ form one parameter subclasses of the Kneser graphs and bipartite Kneser graphs respectively. In particular both classes are vertex transitive while resisting definitive…

Combinatorics · Mathematics 2016-11-22 Timothy J. Frye

We call an oriented odd cycle alternating if it has exactly one vertex whose in-degree and out-degree are both positive. In this paper, we investigate whether certain graphs admit an orientation that avoids alternating odd cycles as…

Combinatorics · Mathematics 2025-08-27 Nóra Almási , Gábor Simonyi

We study permutations on n elements preserving orientation (parity) of every subset of size k. We describe all groups of these permutations. Unexpectedly, these groups (except for some special cases) are either trivial, cyclic or dihedral.…

Combinatorics · Mathematics 2025-01-24 Vitor Fernandes , Alexei Vernitski