Results 41 to 50 of about 98,708 (229)
Combinatorics in the Art of the Twentieth Century [PDF]
This paper is motivated by a question I asked myself: How can combinatorial structures be used in a work of art? Immediately, other questions arose: Whether there are artists that work or think combinatorially?
Barrière Figueroa, Eulalia
core
Faber's socle intersection numbers via Gromov–Witten theory of elliptic curve
Abstract The goal of this very short note is to give a new proof of Faber's formula for the socle intersection numbers in the tautological ring of Mg$\mathcal {M}_g$. This new proof exhibits a new beautiful tautological relation that stems from the recent work of Oberdieck–Pixton on the Gromov–Witten theory of the elliptic curve via a refinement of ...
Xavier Blot+2 more
wiley +1 more source
Obstructions to combinatorial formulas for plethysm
Motivated by questions of Mulmuley and Stanley we investigate quasi-polynomials arising in formulas for plethysm. We demonstrate, on the examples of $S^3(S^k)$ and $S^k(S^3)$, that these need not be counting functions of inhomogeneous polytopes of ...
Kahle, Thomas, Michalek, Mateusz
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The weak Lefschetz property for artinian Gorenstein algebras
Abstract It is an extremely elusive problem to determine which standard artinian graded K$K$‐algebras satisfy the weak Lefschetz property (WLP). Codimension 2 artinian Gorenstein graded K$K$‐algebras have the WLP and it is open to what extent such result might work for codimension 3 artinian Gorenstein graded K$K$‐algebras.
Rosa M. Miró‐Roig
wiley +1 more source
A simple proof for the number of tilings of quartered Aztec diamonds [PDF]
We get four quartered Aztec diamonds by dividing an Aztec diamond region by two zigzag cuts passing its center. W. Jockusch and J. Propp (in an unpublished work) found that the number of tilings of quartered Aztec diamonds is given by simple product ...
Lai, Tri
core +1 more source
Normal covering numbers for Sn$S_n$ and An$A_n$ and additive combinatorics
Abstract The normal covering number γ(G)$\gamma (G)$ of a noncyclic group G$G$ is the minimum number of proper subgroups whose conjugates cover the group. We give various estimates for γ(Sn)$\gamma (S_n)$ and γ(An)$\gamma (A_n)$ depending on the arithmetic structure of n$n$. In particular we determine the limsups over γ(Sn)/n$\gamma (S_n) / n$ and γ(An)
Sean Eberhard, Connor Mellon
wiley +1 more source
Indiscernibles in monadically NIP theories
Abstract We prove various results around indiscernibles in monadically NIP theories. First, we provide several characterizations of monadic NIP in terms of indiscernibles, mirroring previous characterizations in terms of the behavior of finite satisfiability. Second, we study (monadic) distality in hereditary classes and complete theories.
Samuel Braunfeld, Michael C. Laskowski
wiley +1 more source
New bounds for equiangular lines
A set of lines in $\mathbb{R}^n$ is called equiangular if the angle between each pair of lines is the same. We address the question of determining the maximum size of equiangular line sets in $\mathbb{R}^n$, using semidefinite programming to improve the ...
Barg, Alexander, Yu, Wei-Hsuan
core +1 more source
Combinatorics: The Mathematics of Fair Thieves and Sophisticated Forgetters [PDF]
Noga Alon
openalex +1 more source
Estimates on the decay of the Laplace–Pólya integral
Abstract The Laplace–Pólya integral, defined by Jn(r)=1π∫−∞∞sincntcos(rt)dt$J_n(r) = \frac{1}{\pi }\int _{-\infty }^\infty \operatorname{sinc}^n t \cos (rt) \,\mathrm{d}t$, appears in several areas of mathematics. We study this quantity by combinatorial methods; accordingly, our investigation focuses on the values at integer rs$r{\rm s}$.
Gergely Ambrus, Barnabás Gárgyán
wiley +1 more source