Results 11 to 20 of about 317,927 (261)

On the geometry of stack-sorting simplices [PDF]

The American Journal of Combinatorics
We show that all stack-sorting polytopes are simplices. Furthermore, we show that the stack-sorting polytopes generated from permutations of the form \(Ln1\) have relative volume 1.
Cameron Ake, Spencer Lewis, Amanda Louie, Andrés Vindas Meléndez   +3 more
doaj   +4 more sources

Stack-sorting for Coxeter groups [PDF]

Combinatorial Theory, 2022
39 pages, 11 figures; to be published in Combinatorial ...
Defant, Colin
exaly   +7 more sources

Stack-Sorting Grammar [PDF]

Nordlyd: Tromsø University Working Papers on Language & Linguistics
I propose that, within local domains corresponding to extended projections, typologically possible information-neutral word orders are limited to the stack-sortable (231-avoiding) permutations of a universal head-complement-specifier linear order.
David P. Medeiros
doaj   +3 more sources

Stack-sorting with stacks avoiding vincular patterns

Discrete Mathematics
We introduce the stack-sorting map $\text{SC}_σ$ that sorts, in a right-greedy manner, an input permutation through a stack that avoids some vincular pattern $σ$. The stack-sorting maps of Cerbai et al. in which the stack avoids a pattern classically and Defant and Zheng in which the stack avoids a pattern consecutively follow as special cases.
Zhao, William
exaly   +5 more sources

A new lower bound for deterministic pop-stack-sorting [PDF]

European Journal of Combinatorics
European Journal of ...
Keith Copenhaver
exaly   +6 more sources

Fertility monotonicity and average complexity of the stack-sorting map

European Journal of Combinatorics, 2021
17 pages, 4 ...
Colin Defant
exaly   +4 more sources

The pop-stack-sorting operator on Tamari lattices

Advances in Applied Mathematics, 2022
Motivated by the pop-stack-sorting map on the symmetric groups, Defant defined an operator $\mathsf{Pop}_M : M \to M$ for each complete meet-semilattice $M$ by $$\mathsf{Pop}_M(x)=\bigwedge(\{y\in M: y\lessdot x\}\cup \{x\}).$$ This paper concerns the dynamics of $\mathsf{Pop}_{\mathrm{Tam}_n}$, where $\mathrm{Tam}_n$ is the $n$-th Tamari lattice.
Letong Hong
exaly   +4 more sources

The order of the (123, 132)-avoiding stack sort

Enumerative Combinatorics and Applications
Let $s$ be West's deterministic stack-sorting map. A well-known result (West) is that any length $n$ permutation can be sorted with $n-1$ iterations of $s.$ In 2020, Defant introduced the notion of highly-sorted permutations -- permutations in $s^t(S_n)$ for $t \lessapprox n-1.$ In 2023, Choi and Choi extended this notion to generalized stack-sorting ...
Owen Zhang
doaj   +3 more sources

HMQ-ES-Stack-GBR: A Hybrid Ensemble Learning Model for Mechanical and Physical Quality Prediction in FDM 3D Printing [PDF]

Micromachines
In Fusion Deposition Modeling-based manufacturing, process parameters affect the mechanical and physical properties of the print. Considering these properties, accurately predicting print quality is essential.
Elif Aktepe, Uçman Ergün
doaj   +2 more sources

Poset Associahedra and Stack-sorting

, 2023
For any finite connected poset $P$, Galashin introduced a simple convex $(|P|-2)$-dimensional polytope $\mathscr{A}(P)$ called the poset associahedron. For a certain family of posets, whose poset associahedra interpolate between the classical permutohedron and associahedron, we give a simple combinatorial interpretation of the $h$-vector.
Nguyen, Son, Sack, Andrew
openaire   +3 more sources