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A research for a general expression of the triplets of integer sided triangles with a $120^{\circ}$ angle, in parallel with the case of a $60^{\circ}$ angle.

General Mathematics · Mathematics 2025-10-17 Yasushi Ieno

The aim of the present paper is to provide an intrinsic investigation of projective changes in Finlser geometry, following the pullback formalism. Various known local results are generalized and other new intrinsic results are obtained.…

Differential Geometry · Mathematics 2013-04-29 Nabil L. Youssef , S. H. Abed , A. Soleiman

For some values of the degrees of the equations, we show, using geometric invariant theory, that the coarse moduli space of smooth complete intersections in P^N is quasi-projective. ----- Pour certaines valeurs des degres des equations, on…

Algebraic Geometry · Mathematics 2019-11-11 Olivier Benoist

In this paper, we study the alternating Euler $T$-sums and related sums by using the method of contour integration. We establish the explicit formulas for all linear and quadratic Euler $T$-sums and related sums. Some interesting new…

Number Theory · Mathematics 2020-06-22 Weiping Wang , Ce Xu

In this article, we will introduce methods of non-standard analysis into projective geometry. Especially, we will analyze the properties of a projective space over a non-Archimedean field. Non-Archimedean fields contain numbers that are…

Algebraic Geometry · Mathematics 2018-04-06 Michael Strobel

Geometric optimization problems are at the core of many applications in geometry processing. The choice of a representation fitting an optimization problem can considerably simplify solving the problem. We consider the Nonlinear…

Numerical Analysis · Mathematics 2020-04-29 Josua Sassen , Behrend Heeren , Klaus Hildebrandt , Martin Rumpf

A point in the interior of a planar triangle determines a subdivision into six subtriangles. A triangle with angles commensurable with $\pi$ is called $\pi$-commensurable. For such a triangle a subdivision where each of the subtriangles are…

Metric Geometry · Mathematics 2022-06-10 Hasan Korkmaz , Ferit Öztürk

We begin by introducing an algebraic structure with three constants and one ternary operation to which we call mobi algebra. This structure has been designed to capture the most relevant properties of the unit interval that are needed in…

Rings and Algebras · Mathematics 2018-01-09 J. P. Fatelo , N. Martins-Ferreira

Author developed a uniform model for different spaces where distance and angle measure kinds are parameters. This model is calculus centric, but can also be used in theoretical research. It is useful in the following domains: deduction of…

Metric Geometry · Mathematics 2018-07-30 Alexandru Popa

We investigate the relation of the Lie point symmetries for the geodesic equations with the collineations of decomposable spacetimes. We review previous results in the literature on the Lie point symmetries of the geodesic equations and we…

General Relativity and Quantum Cosmology · Physics 2021-06-23 Andronikos Paliathanasis

This is a corrected version of my paper "Application of integral geometry to minimal surfaces" appeared in International J. Math. vol. 4 Nr. 1 (1993), 89-111. The correction concerns Proposition 3.5. We discuss this correction in Appendix…

Differential Geometry · Mathematics 2014-01-22 Hông Vân Lê

Let $S$ be a Riemann surface of analytic finite type or the unit disk in the complex plane. Let $[\mu]$ denote the Teichm\"uller equivalence classes of Beltrami differentials $\mu $. We apply the Fundamental Inequalities to obtain a binary…

Complex Variables · Mathematics 2009-02-16 Guowu Yao

We give a geometric interpretation of all the $m$-th elliptic integrable systems associated to a $k'$-symmetric space $N=G/G_0$ (in the sense of C.L. Terng). It turns out that we have to introduce the integer $m_{k'}$ defined by m_{1}=0 and…

Differential Geometry · Mathematics 2011-04-18 Idrisse Khemar

This paper introduces the geodesics of triangulated image object shapes. Both rectilinear and curvilinear triangulations of shapes are considered. The triangulation of image object shapes leads to collections of what are known as nerve…

Computational Geometry · Computer Science 2017-08-25 M. Z. Ahmad , J. F. Peters

We compute the sum and the alternating sum of the reciprocals of triangular numbers using two standard methods from calculus: a telescoping series approach and a power series approach. We then extend these results to generalized…

Number Theory · Mathematics 2026-02-06 Pawel Grzegrzolka , Jeffrey L. Meyer

The linking integral is an invariant of the link-type of two manifolds immersed in a Euclidean space. It is shown that the ordinary Gauss integral in three dimensions may be simplified to a winding number integral in two dimensions. This…

Differential Geometry · Mathematics 2009-07-21 Daniel J. Cross

In this survey article, we are interested on minimal triangulations of closed pl manifolds. We present a brief survey on the works done in last 25 years on the following: (i) Finding the minimal number of vertices required to triangulate a…

Geometric Topology · Mathematics 2007-05-23 Basudeb Datta

Closed form solutions for the computation of the solid angle from polygonal cross-sections are well known, however similar formulae for computation of projected solid angle are not generally available. Formulae for computing the projected…

Optics · Physics 2022-05-25 Brett A. Cruden

$\SLR$ geometry is one of the eight 3-dimensional Thurston geometries, it can be derived from the 3-dimensional Lie group of all $2\times 2$ real matrices with determinant one. Our aim is to describe and visualize the {\it regular infinite…

Metric Geometry · Mathematics 2016-08-14 Jenő Szirmai

In this article, gentle algebras are realised as tiling algebras, which are associated to partial triangulations of unpunctured surfaces with marked points on the boundary. This notion of tiling algebras generalise the notion of Jacobian…

Representation Theory · Mathematics 2018-03-16 Karin Baur , Raquel Coelho Simoes