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Related papers: Insolvability of $x^x = a$ in elementary functions

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In this note, we give a simple proof that the Riemann Hypothesis is unprovable in any reasonable axiom system.

General Mathematics · Mathematics 2011-11-24 Craig Alan Feinstein

We first reformulate and expand with several novel findings some of the basic results in the integrability of Abel equations. Next, these results are applied to Vein's Abel equation whose solutions are expressed in terms of the third order…

Classical Analysis and ODEs · Mathematics 2016-04-04 Stefan C. Mancas , Haret C Rosu

We study orbit-finite systems of linear equations, in the setting of sets with atoms. Our principal contribution is a decision procedure for solvability of such systems. The procedure works for every field (and even commutative ring) under…

Computation and Language · Computer Science 2024-02-28 Arka Ghosh , Piotr Hofman , Sławomir Lasota

In this paper we consider a fragment of the first-order theory of the real numbers that includes systems of equations of continuous functions in bounded domains, and for which all functions are computable in the sense that it is possible to…

Computational Complexity · Computer Science 2016-08-15 Peter Franek , Stefan Ratschan , Piotr Zgliczynski

We provide an analytical closed-form solution of the exponential equation $a^x+a^{-x}=x$ for a specific value $a$, discuss the number of roots in general case, and provide bounds on the roots.

History and Overview · Mathematics 2014-01-23 Ondrej Slučiak

Iterative equation is an equality with an unknown function and its iterates. There were not found a result on iterative equations with multiplication of iterates of the unknown function on $\mathbb{R}$. In this paper we use an exponential…

Dynamical Systems · Mathematics 2021-05-10 Chaitanya Gopalakrishna , Murugan Veerapazham , Suyun Wang , Weinian Zhang

We prove that all entire transcendental entire functions have infinite topological entropy.

Dynamical Systems · Mathematics 2020-11-25 Anna Miriam Benini , John Erik Fornæss , Han Peters

The analysis of solutions to algebraic equations is further simplified. A couple of functions and their analytic continuation or root findings are required.

General Physics · Physics 2007-05-23 Gordon Chalmers

We investigate errors in tangents and adjoints of implicit functions resulting from errors in the primal solution due to approximations computed by a numerical solver. Adjoints of systems of linear equations turn out to be unconditionally…

Numerical Analysis · Mathematics 2021-09-06 Uwe Naumann

We consider a generalization of a functional equation that models the learning process in various animal species. The equation can be considered nonlocal, as it is built with a convex combination of the unknown function evaluated at mixed…

Numerical Analysis · Mathematics 2025-02-24 Josefa Caballero , Hanna Okrasińska-Płociniczak , Łukasz Płociniczak , Kishin Sadarangani

A system of singular integral equations with monotone and concave nonlinearity in the subcritical case is investigated. The specified system and its scalar analog have direct applications in various areas of physics and biology. In…

Functional Analysis · Mathematics 2024-10-28 A. Kh. Khachatryan , Kh. A. Khachatryan , H. S. Petrosyan

Cost functions provide a framework for constructions of sets Turing below the halting problem that are close to computable. We carry out a systematic study of cost functions. We relate their algebraic properties to their expressive…

Logic · Mathematics 2017-03-07 Andre Nies

The interrelation between analytic functions and real-valued functions is formulated in the work. It is shown such an interrelation realizes nonlinear representations for real-valued functions that allows to develop new methods of…

Mathematical Physics · Physics 2021-06-01 Asset Durmagambetov

Let $f(x)=x^TAx+2a^Tx+c$ and $h(x)=x^TBx+2b^Tx+d$ be two quadratic functions having symmetric matrices $A$ and $B$. The S-lemma with equality asks when the unsolvability of the system $f(x)<0, h(x)=0$ implies the existence of a real number…

Optimization and Control · Mathematics 2015-04-20 Yong Xia , Shu Wang , Ruey-Lin Sheu

In this paper we present another proof of the analytic version of the Hahn-Banach theorem in terms of convex functionals.

Functional Analysis · Mathematics 2020-03-19 Sokol Bush Kaliaj

In this paper, we associate to each positive number k a new class of endomorphisms of the sheaf of germs of holomorphic functions on [-1,1] and prove the solvability in the Gevrey class G_k([-1,1]) of some linear functional equations…

Complex Variables · Mathematics 2019-02-06 Elmostafa Bendib , Hicham Zoubeir

We extend the classical notion of solvability to a lambda-calculus equipped with pattern matching. We prove that solvability can be characterized by means of typability and inhabitation in an intersection type system P based on…

Logic in Computer Science · Computer Science 2023-06-22 Antonio Bucciarelli , Delia Kesner , Simona Ronchi Della Rocca

It has been proved by the author [arXiv: 2404.19433] that the Arens-Michael envelope of a solvable Lie algebra is a homological epimorphism. We show here that for algebras of analytic functionals on a connected complex Lie group the…

Functional Analysis · Mathematics 2026-05-26 Oleg Aristov

A systematic study of the trigonometric equation A tan a + B sin b = C, where A, B and C^2 are rational numbers. The special case tan Pi/11 + 4 sin 3 Pi/11 = sqrt[11] appears in the classical literature.

Number Theory · Mathematics 2007-09-25 Victor H. Moll

The aim of this paper is twofold. On one hand, the additive solvability of the system of functional equations \[d_{k}(xy)=\sum_{i=0}^{k}\Gamma(i,k-i) d_{i}(x)d_{k-i}(y) \qquad (x,y\in \R,\,k\in\{0,\ldots,n\}) \] is studied, where…

Commutative Algebra · Mathematics 2014-03-17 Eszter Gselmann , Zsolt Páles