Results 11 to 20 of about 292 (180)
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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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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Uniqueness of L-Functions Concerning Certain Differential Polynomials
Discrete Dynamics in Nature and Society, 2018 Relying on Nevanlinna theory and the properties of L-functions in the extended Selberg class, we mainly study the uniqueness problems on L-functions concerning certain differential polynomials. This generalizes some results of Steuding, Li, Fang, and Liu-
Wen-Jie Hao, Jun-Fan Chen
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Robust Controller Design Using the Nevanlinna-Pick Interpolation in Gyro Stabilized Pod
Discrete Dynamics in Nature and Society, 2010 The sensitivity minimization of feedback system is solved based on the theory of Nevanlinna-Pick interpolation with degree constraint without using weighting functions. More details of the dynamic characteristic of second-order system investigated, which
Bin Liu +3 more
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Nevanlinna analytic continuation for Migdal–Eliashberg theory
Computational Materials TodayIn this work, we present a method to reconstruct real-frequency properties from analytically continued causal Green’s functions within the framework of Migdal–Eliashberg (ME) theory for superconductivity.
D.M. Khodachenko +4 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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Value Distribution for a Class of Small Functions in the Unit Disk
International Journal of Mathematics and Mathematical Sciences, 2011 If 𝑓 is a meromorphic function in the complex plane, R. Nevanlinna noted that its characteristic function 𝑇(𝑟,𝑓) could be used to categorize 𝑓 according to its rate of growth as |𝑧|=𝑟→∞. Later H.
Paul A. Gunsul
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The q-Difference Theorems for Meromorphic Functions of Several Variables
Abstract and Applied Analysis, 2014 We investigate q-shift analogue of the lemma on logarithmic derivative of several variables. Let f be a meromorphic function in ℂn of zero order such that f(0)≠0, ∞, and let q∈ℂn\{0}.
Zhi-Tao Wen
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