English
Related papers

Related papers: A vector identity for quadrilaterals

200 papers

We describe a method for counting the number of $1$-connected trivalent $2$-stratifolds with a given number of singular curves and $2$-manifold components.

Geometric Topology · Mathematics 2020-12-09 J. C. Gómez-Larrañaga , F. González-Acuña , Wolfgang Heil

This article provides a simple proof of the quadratic formula, which also produces an efficient and natural method for solving general quadratic equations. The derivation is computationally light and conceptually natural, and has the…

History and Overview · Mathematics 2019-12-17 Po-Shen Loh

The question of whether a split tensor product of quaternion algebras with involution over a field of characteristic two can be expressed as a tensor product of split quaternion algebras with involution, is shown to have an affirmative…

Rings and Algebras · Mathematics 2015-08-11 M. G. Mahmoudi , A. -H. Nokhodkar

We discuss the notion of the orbifold transform, and illustrate it on simple examples. The basic properties of the transform are presented, including transitivity and the exponential formula for symmetric products. The connection with the…

Group Theory · Mathematics 2009-11-13 P. Bantay

We prove a simple inequality for a sum of squares of norms of two vectors in an inner product space. Next, using this inequality we derive the so--called "reverse uncertainty relation" and analyze its properties.

Quantum Physics · Physics 2026-05-28 K. Urbanowski

A quadrilateral of factors is an irreducible inclusion of factors $N \subset M$ with intermediate subfactors $P$ and $Q$ such that $P$ and $Q$ generate $M$ and the intersection of $P$ and $Q$ is $N$. We investigate the structure of a…

Operator Algebras · Mathematics 2007-05-23 Pinhas Grossman , Masaki Izumi

We present a new partition identity and give a combinatorial proof of our result. This generalizes a result of Andrew's in which he considers the generation function for partitions with respect to size, number of odd parts, and number of…

Combinatorics · Mathematics 2007-05-23 Cilanne E. Boulet

In this paper we introduce the intuitive notion of trivergence of probability distributions (TPD). This notion allow us to calculate the similarity among triplets of objects. For this computation, we can use the well known measures of…

Information Theory · Computer Science 2015-06-23 Juan-Manuel Torres-Moreno

The visibility graph of a simple polygon represents visibility relations between its vertices. Knowing the correct order of the vertices around the boundary of a polygon and its visibility graph, it is an open problem to locate the vertices…

Computational Geometry · Computer Science 2019-05-03 Sahar Mehrpour , Alireza Zarei

A probability method is provided to prove three classes of combinatorial identities. The method is extremely simple, only one step after the proper probability setup.

Combinatorics · Mathematics 2009-11-02 Tong Zhu

The diagonals of a quadrilateral form four associated triangles, called half triangles. Each half triangle is bounded by two sides of the quadrilateral and one diagonal. If we locate a triangle center (such as the incenter, centroid,…

General Mathematics · Mathematics 2025-06-24 Stanley Rabinowitz , Ercole Suppa

This short note delivers, via elementary calculations, a product representation of pi.

Number Theory · Mathematics 2020-01-22 S. R. Holcombe

We develop a theory of simple pentagonal subdivision of quadrilateral tilings, on orientable as well as non-orientable surfaces. Then we apply the theory to answer questions related to pentagonal tilings of surfaces, especially those…

Combinatorics · Mathematics 2019-08-23 Min Yan

The triangulations of a regular convex polygon are enumerated according to the number of diagonals parallel to a fixed edge. The enumeration uses the Shapiro convolution identity, as well as an interpretation of this identity in terms of…

Combinatorics · Mathematics 2012-08-21 Alon Regev

We give a short derivation of an identity of Bridgeman concerning orthospectra of hyperbolic surfaces.

Geometric Topology · Mathematics 2010-09-06 Danny Calegari

An expression for four-tangle is obtained by examining the negativity fonts present in a four-way partial transpose under local unitary operations. An alternate derivation of three tangle is also given.

Quantum Physics · Physics 2010-08-06 S. Shelly Sharma , N. K. Sharma

An identity for binomial symbols modulo an odd positive integer $n$ relating to the least prime factor of $n$ is proved. The identity is discussed within the context of Pell conics.

Number Theory · Mathematics 2011-07-29 Samuel A. Hambleton

Given two combinatorial identities proved earlier, a new set of variations of these combinatorial identities is listed and proved with the integral representation method. Some identities from literature are shown to be special cases of…

Combinatorics · Mathematics 2017-05-17 M. J. Kronenburg

We discuss an unusual phenomenon in (integral) positive ternary quadratic forms. We also describe an interesting pairing of genera of ternary forms.

Number Theory · Mathematics 2012-05-11 William C. Jagy

It is shown that the unique representation of positive integers in terms of tribonacci numbers and the unique representation in terms of iterated A, B and C sequences defined from the tribonacci word are equivalent. Two auxiliary…

Number Theory · Mathematics 2020-09-25 Wolfdieter Lang