Results 21 to 30 of about 5,990,008 (247)
Composition operators on weighted Hilbert spaces of Dirichlet series
Journal of the London Mathematical Society, Volume 108, Issue 2, Page 837-868, August 2023., 2023 Abstract We study composition operators of characteristic zero on weighted Hilbert spaces of Dirichlet series. For this purpose, we demonstrate the existence of weighted mean counting functions associated with the Dirichlet series symbol, and provide a corresponding change of variables formula for the composition operator.
Athanasios Kouroupis +1 more
wiley +1 more source
PAMM, Volume 22, Issue 1, March 2023., 2023 Abstract Classical hardness of approximation (HA) is the phenomenon that, assuming P ≠ NP, one can easily compute an ϵ‐approximation to the solution of a discrete computational problem for ϵ > ϵ0 > 0, but for ϵ < ϵ0 – where ϵ0 is the approximation threshold – it becomes intractable. Recently, a similar yet more general phenomenon has been documented in
Laura Thesing, Anders C. Hansen
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Bulletin of the London Mathematical Society, Volume 55, Issue 1, Page 1-77, February 2023., 2023 Abstract An exponential polynomial is a finite linear sum of terms P(z)eQ(z)$P(z)e^{Q(z)}$, where P(z)$P(z)$ and Q(z)$Q(z)$ are polynomials. The early results on the value distribution of exponential polynomials can be traced back to Georg Pólya's paper published in 1920, while the latest results have come out in 2022.
Janne Heittokangas +3 more
wiley +1 more source
Limit Directions of Julia Sets of Entire Functions and Complex Differential Equations
Journal of Mathematics, Volume 2023, Issue 1, 2023., 2023 The limiting directions of Julia sets of infinite order entire functions are studied by combining the theory of complex dynamic system and the theory of complex differential equations, in which the lower bound of the measure of limiting direction of Julia set of entire solutions of complex differential equations is obtained.
Zhigao Qin +3 more
wiley +1 more source
Extreme problems in the space of meromorphic functions of finite order in the half plane. II
Математичні Студії, 2020 The extremal problems in the space of meromorphic functions of order $\rho>0$ in upper half-plane are studed. The method for studying is based on the theory of Fourier coefficients of meromorphic functions.
K.G. Malyutin, A.A. Revenko
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On the equation fn + (f″)m ≡ 1
Demonstratio Mathematica, 2023 Let nn and mm be two positive integers, and the second-order Fermat-type functional equation fn+(f″)m≡1{f}^{n}+{({f}^{^{\prime\prime} })}^{m}\equiv 1 does not have a nonconstant meromorphic solution in the complex plane, except (n,m)∈{(1,1),(1,2),(1,3 ...
Dang Guoqiang
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AIMS Mathematics, 2021 In this paper, we study the transcendental entire solutions for the nonlinear differential-difference equations of the forms: $ \begin{eqnarray*} f^{2}(z)+\widetilde{\omega} f(z)f'(z)+q(z)e^{Q(z)}f(z+c) = u(z)e^{v(z)}, \end{eqnarray*} $ and $ \
Nan Li, Jiachuan Geng, Lianzhong Yang
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On the differentiability of T(r,f)
International Journal of Mathematics and Mathematical Sciences, 1982 It is well known that T(r,f) is differentiable at least for r>r0. We show that, in fact, T(r,f) is differentiable for all but at most one value of r, and if T(r,f) fails to have a derivative for some value of r, then f is a constant times a quotient of ...
Douglas W. Townsed
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Some Properties of Meromorphic Solutions of Systems of Complex q-Shift Difference Equations
Abstract and Applied Analysis, 2013 In view of Nevanlinna theory, we study the properties of meromorphic solutions of systems of a class of complex difference equations. Some results obtained improve and extend the previous theorems given by Gao.
Hong-Yan Xu +2 more
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Entire solutions for several general quadratic trinomial differential difference equations
Open Mathematics, 2021 This paper is devoted to exploring the existence and the forms of entire solutions of several quadratic trinomial differential difference equations with more general forms.
Luo Jun, Xu Hong Yan, Hu Fen
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