The number of set-orbits of a solvable permutation group

A permutation group 𝐺 acting on a set Ω induces a permutation action on the power set P ⁢ ( Ω ) \mathscr{P}(\Omega) (the set of all subsets of Ω). Let 𝐺 be a finite permutation group of degree 𝑛, and let s ⁢ ( G ) s(G) denote the number of orbits of 𝐺 on P ⁢ ( Ω ) \mathscr{P}(\Omega) . In this paper, we give the explicit lower bound of log 2 ⁡ s ⁢ ( G ) / log 2 ⁡ | G | \log_{2}s(G)/{\log_{2}\lvert G\rvert} over all solvable groups 𝐺. As applications, we first give an explicit bound of a result of Keller for estimating the number of conjugacy classes, and then we combine it with the McKay conjecture to estimate the number of p ′ p^{\prime} -degree irreducible representations of a solvable group.

Some generalizations of delay integral inequalities of Gronwall-Bellman type with power and their applications

<p style='text-indent:20px;'>Noting the diverse generalizations of the Gronwall-Bellman inequality, this paper investigates some new delay integral inequalities with power, deriving explicit bound on the solution and providing an example. The inequalities given here can act as powerful tools for studying qualitative properties such as existence, uniqueness, boundedness, stability and asymptotics of solutions of differential and integral equations.</p>

ON DEL PEZZO FIBRATIONS IN POSITIVE CHARACTERISTIC

We establish two results on three-dimensional del Pezzo fibrations in positive characteristic. First, we give an explicit bound for torsion index of relatively torsion line bundles. Second, we show the existence of purely inseparable sections with explicit bounded degree. To prove these results, we study log del Pezzo surfaces defined over imperfect fields.

Some generalizations of linear finite difference inequalities of Pachpatte type

In this paper, we establish some linear finite difference inequalities and obtain an explicit bound on the unknown function. These inequalities can be used as handy tools to study the qualitative as well as the quantitative properties of solutions of some finite difference equations and its variants.

Algorithm for filling curves on surfaces

Let $$\varSigma $$ Σ be a compact, orientable surface of negative Euler characteristic, and let h be a complete hyperbolic metric on $$\varSigma $$ Σ . A geodesic curve $$\gamma $$ γ in $$\varSigma $$ Σ is filling if it cuts the surface into topological disks and annuli. We propose an efficient algorithm for deciding whether a geodesic curve, represented as a word in some generators of $$\pi _1(\varSigma )$$ π 1 ( Σ ) , is filling. In the process, we find an explicit bound for the combinatorial length of a curve given by its Dehn–Thurston coordinate, in terms of the hyperbolic length. This gives us an efficient method for producing a collection which is guaranteed to contain all words corresponding to simple geodesics of bounded hyperbolic length.

An aspect of optimal regression design for LSMC

Practitioners sometimes suggest to use a combination of Sobol sequences and orthonormal polynomials when applying an LSMC algorithm for evaluation of option prices or in the context of risk capital calculation under the Solvency II regime. In this paper, we give a theoretical justification why good implementations of an LSMC algorithm should indeed combine these two features in order to assure numerical stability. Moreover, an explicit bound for the number of outer scenarios necessary to guarantee a prescribed degree of numerical stability is derived. We embed our observations into a coherent presentation of the theoretical background of LSMC in the insurance setting.

An Explicit Manin-Dem’janenko Theorem in Elliptic Curves

Let be a curve of genus at least 2 embedded in E1 × … × EN, where the Ei are elliptic curves for i = 1, . . . , N. In this article we give an explicit sharp bound for the Néron–Tate height of the points of contained in the union of all algebraic subgroups of dimension < max(), where is the minimal dimension of a translate (resp. of a torsion variety) containing .As a corollary, we give an explicit bound for the height of the rational points of special curves, proving new cases of the explicit Mordell Conjecture and in particular making explicit (and slightly more general in the CM case) the Manin–Dem’janenko method for curves in products of elliptic curves.

IMPROVING AN INEQUALITY FOR THE DIVISOR FUNCTION

Using elementary means, we improve an explicit bound on the divisor function due to Friedlander and Iwaniec [Opera de Cribro, American Mathematical Society, Providence, RI, 2010]. Consequently, we modestly improve a result regarding a sieving inequality for Gaussian sequences.