English
Related papers

Related papers: On approximately Convex and Affine Sequences

200 papers

Consider a sum of convex functions, where the only information known about each individual summand is the location of a minimizer. In this work, we give an exact characterization of the set of possible minimizers of the sum. Our results…

Optimization and Control · Mathematics 2024-03-11 Moslem Zamani , François Glineur , Julien M. Hendrickx

A permutation sequence is said to be convergent if the density of occurrences of every fixed permutation in the elements of the sequence converges. We prove that such a convergent sequence has a natural limit object, namely a Lebesgue…

We construct a sequence that converges to a solution of the Cauchy problem for a singularly perturbed linear inhomogeneous differential equation of an arbitrary order. This sequence is also an asymptotic sequence in the following sense: the…

Classical Analysis and ODEs · Mathematics 2017-11-23 Evgeny E. Bukzhalev , Alexey V. Ovchinnikov

A method of numerically evaluating slowly convergent monotone series is described. First, we apply a condensation transformation due to Van Wijngaarden to the original series. This transforms the original monotone series into an alternating…

Numerical Analysis · Mathematics 2025-10-20 U. D. Jentschura , P. J. Mohr , G. Soff , E. J. Weniger

We introduce and study a new class of generalized convex functions termed star quasiconvex functions. This class includes convex, star-convex, quasiconvex, quasar-convex, and positively homogeneous functions of any degree $p>0$ as special…

Optimization and Control · Mathematics 2026-05-27 Phan Quoc Khanh , Felipe Lara

We study asymmetric regular types. If $\frak p$ is regular and $A$-asymmetric then there exists a strict order such that Morley sequences in $\frak p$ over $A$ are strictly increasing (we allow Morley sequences to be indexed by elements of…

Logic · Mathematics 2015-03-17 Slavko Moconja , Predrag Tanović

If $(X,J)$ is an almost complex manifold, then a function $u$ is said to be plurisubharmonic on $X$ if it is upper semi-continuous and its restriction to every local pseudo-holomorphic curve is subharmonic. As in the complex case, it is…

Differential Geometry · Mathematics 2009-09-29 Nefton Pali

We solve a randomized version of the following open question: is there a strictly convex, bounded curve \gamma in the plane such that the number of rational points on \gamma, with denominator $n$, approaches infinity with $n$? Although this…

Metric Geometry · Mathematics 2019-02-20 Nick Gravin , Fedor Petrov , Sinai Robins , Dmitry Shiryaev

We consider a type of nonnormal approximation of infinitely divisible distributions that incorporates compound Poisson, Gamma, and normal distributions. The approximation relies on achieving higher orders of cumulant matching, to obtain…

Probability · Mathematics 2013-04-24 Zhiyi Chi

In this paper, we introduce and investigate the concepts of down continuity and down compactness. A real valued function $f$ on a subset $E$ of $\R$, the set of real numbers is down continuous if it preserves downward half Cauchy sequences,…

Functional Analysis · Mathematics 2018-02-06 Huseyin Cakalli

We prove that if $u:\mathbb{R}^n\to\mathbb{R}$ is strongly convex, then for every $\varepsilon>0$ there is a strongly convex function $v\in C^2(\mathbb{R}^n)$ such that $|\{u\neq v\}|<\varepsilon$ and $\Vert u-v\Vert_\infty<\varepsilon$.

Classical Analysis and ODEs · Mathematics 2024-03-26 Daniel Azagra , Marjorie Drake , Piotr Hajłasz

The main point of this paper is to prove the following useful result: If the almost everywhere 2-jet of a locally quasi-convex function u satisfies a degenerate elliptic constraint F, then u is F-subharmonic, i.e., u is a viscosity…

Analysis of PDEs · Mathematics 2016-08-02 F. Reese Harvey , H. Blaine Lawson

A new notion of thickness for subsets of $B[0,1]\subset \mathbb{R}^n$ called affine thickness is defined; this notion of thickness is a generalisation of Falconer-Yavicoli thickness and is adapted to be used in the study of certain sets…

Metric Geometry · Mathematics 2026-01-26 Richard A. Howat

This paper addresses the fundamental question of when convex sets remain disjoint after random projection. We provide an analysis using ideas from high-dimensional convex geometry. For ellipsoids, we provide a bound in terms of the distance…

Machine Learning · Computer Science 2014-04-14 Afonso S. Bandeira , Dustin G. Mixon , Benjamin Recht

The convex hull of the subgraph of the prime counting function $x\rightarrow \pi(x)$ is a convex set, bounded from above by a graph of some piecewise affine function $x\rightarrow \epsilon(x)$. The vertices of this function form an infinite…

Number Theory · Mathematics 2014-08-18 Edward Tutaj

We study the finite convergence of iterative methods for solving convex feasibility problems. Our key assumptions are that the interior of the solution set is nonempty and that certain overrelaxation parameters converge to zero, but with a…

Optimization and Control · Mathematics 2021-07-13 Victor I. Kolobov , Simeon Reich , Rafał Zalas

For a continuous flow on a compact metric space, the aim of this paper is to prove a Conley-type decomposition of the strong chain recurrent set. We first discuss in details the main properties of strong chain recurrent sets. We then…

Dynamical Systems · Mathematics 2019-03-27 Olga Bernardi , Anna Florio

Suppose $a_n$ is a real, nonnegative sequence that does not increase exponentially. For any $p<1$ we contruct a Lebesgue measurable set $E \subseteq \mathbb{R}$ which has measure at least $p$ in any unit interval and which contains no…

Classical Analysis and ODEs · Mathematics 2024-12-18 Mihail N. Kolountzakis , Effie Papageorgiou

We prove that if f : R^N --> R is quasiconvex and U is open in the density topology of R^N, then sup_U f = ess sup_U f, while inf_U f = ess inf_U f if and only if the equality holds when U = R^N. The first (second) property is typical of…

Metric Geometry · Mathematics 2019-08-15 Patrick J. Rabier

Convergence problems occur abundantly in all branches of mathematics or in the mathematical treatment of the sciences. Sequence transformations are principal tools to overcome convergence problems of the kind. They accomplish this by…

Classical Analysis and ODEs · Mathematics 2007-05-23 Ernst Joachim Weniger