English
Related papers

Related papers: Generalized triangle groups, expanders, and a prob…

200 papers

Many combinatorial and other number triangles are solutions of recurrences of the Graham-Knuth-Patashnik (GKP) type. Such triangles and their defining recurrences are investigated analytically. They are acted on by a transformation group…

Combinatorics · Mathematics 2025-02-17 Robert S. Maier

In the context of algebraic renormalization, the extended antifield formalism is used to derive the general forms of the anomaly consistency condition and of the Callan-Symanzik equation for generic gauge theories. A local version of the…

High Energy Physics - Theory · Physics 2016-09-06 Glenn Barnich

We use the representation theory of the quasisplit form G of SU(3) over a p-adic field to investigate whether certain quotients of the Bruhat--Tits tree associated to this form are Ramanujan bigraphs. We show that a quotient of the tree…

Representation Theory · Mathematics 2010-05-20 Cristina Ballantine , Dan Ciubotaru

In this paper, we present a generalisation of a theorem of David and Rob Pollack. In 'A construction of rigid analytic cohomology classes for congruence subgroups of SL(3,Z)', they give a very general argument for lifting ordinary…

Number Theory · Mathematics 2018-06-18 Chris Williams

Recently, a construction of minimal codes arising from a family of almost Ramanujan graphs was shown. Ramanujan graphs are examples of expander graphs that minimize the second-largest eigenvalue of their adjacency matrix. We call such…

Combinatorics · Mathematics 2026-01-21 Valentino Smaldore

In this article, we investigate the bound of the valency of the Cayley graphs of the generalized quaternion groups which guarantees to be Ramanujan. As is the cases of the cyclic and dihedral groups in our previous studies, we show that the…

Number Theory · Mathematics 2017-08-14 Yoshinori Yamasaki

Recently, the authors with Lea Beneish established a recipe for constructing Ramanujan-Sato series for $1/\pi$, and used this to construct 11 explicit examples of Ramanujan-Sato series arising from modular forms for arithmetic triangle…

Number Theory · Mathematics 2025-03-14 Angelica Babei , Manami Roy , Holly Swisher , Bella Tobin , Fang-Ting Tu

Empirical properties of generating systems for complex reflection groups and their braid groups have been observed by Orlik-Solomon and Brou\'e-Malle-Rouquier, using Shephard-Todd classification. We give a general existence result for…

Group Theory · Mathematics 2009-10-31 David Bessis

Let A be an abelian variety over a number field k. We show that weak approximation holds in the Weil-Ch\^atelet group of A/k but that it may fail when one restricts to the n-torsion subgroup. This failure is however relatively mild; we show…

Number Theory · Mathematics 2015-12-18 Brendan Creutz

We give a recursive construction to produce examples of quadratic forms q_n in the n-th power of the fundamental ideal in the Witt ring whose corresponding adjoint groups PSO(q_n) are not stably rational. Computations of the R-equivalence…

Rings and Algebras · Mathematics 2013-07-09 Nivedita Bhaskhar

We prove a general duality theorem for tangle-like dense objects in combinatorial structures such as graphs and matroids. This paper continues, and assumes familiarity with, the theory developed in [6]

Combinatorics · Mathematics 2014-06-17 Reinhard Diestel , Sang-il Oum

We generalize a parity result of Fleishner and Stiebitz that being combined with Alon--Tarsi polynomial method allowed them to prove that a 4-regular graph formed by a Hamiltonian cycle and several disjoint triangles is always 3-choosable.…

Combinatorics · Mathematics 2015-12-22 Fedor V. Petrov

We show that the pair given by the power set and by the "Grassmannian"(set of all subgroups) of an arbitrary group behaves very much like the pair given by a projective space and its dual projective space. More precisely, we generalize…

Group Theory · Mathematics 2012-01-31 Wolfgang Bertram

We develop a uniform method to derive Chudnovsky-Ramanujan type formulae for triangle groups based on a generalization of a method of Chudnovsky and Chudnovsky; in particular, we carry out the method systematically for non-compact…

Number Theory · Mathematics 2023-11-03 Imin Chen , Gleb Glebov , Ritesh Goenka

We develop a version of Freiman's theorem for a class of non-abelian groups, which includes finite nilpotent, supersolvable and solvable A-groups. To do this we have to replace the small doubling hypothesis with a stronger relative…

Classical Analysis and ODEs · Mathematics 2012-12-04 Tom Sanders

We consider a class of generalized nonexpansive mappings introduced by Karapinar [5] and seen as a generalization of Suzuki (C)-condition. We prove some weak and strong convergence theorems for approximating fixed points of such mappings…

Functional Analysis · Mathematics 2014-03-24 Safeer Hussain Khan , Ibrahim Karahan

Introduced by Kawanaka in order to find the unipotent representations of finite groups of Lie type, generalized Gelfand--Graev characters have remained somewhat mysterious. Even in the case of the finite general linear groups, the…

Representation Theory · Mathematics 2017-11-29 Scott Andrews , Nathaniel Thiem

Using Pascal triangle, we give a simple generalization to the so-called STRAND Puzzle solved by Srinivasa Ramanujan. Thus we are interested in computing the median, first and third quartiles of some integer valued distributions, arising…

Number Theory · Mathematics 2022-02-08 Daniel Gandolfo , Michel Rouleux

We extend previous work on Hrushovski's stabilizer's theorem and prove a measure-theoretic version of a well-known result of Pillay-Scanlon-Wagner on products of three types. This generalizes results of Gowers on products of three sets and…

Logic · Mathematics 2024-05-01 Amador Martin-Pizarro , Daniel Palacín

In this article we generalize a theorem of Benson for generalized quadrangles to strongly regular graphs and directed strongly regular graphs. The main result provides numerical restrictions on the number of fixed vertices and the number of…

Combinatorics · Mathematics 2014-11-14 S. De Winter , E. Kamischke , Z. Wang