Results 1 to 10 of about 228,694 (166)

Approximation of functions of several variables by multidimensional $S$-fractions with independent variables

Karpatsʹkì Matematičnì Publìkacìï, 2021
The paper deals with the problem of approximation of functions of several variables by branched continued fractions. We study the correspondence between formal multiple power series and the so-called "multidimensional $S$-fraction with independent ...
R.I. Dmytryshyn, S.V. Sharyn
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Cramer's rule for implicit linear differential equations over a non-Archimedean ring

Visnik Harkivsʹkogo Nacionalʹnogo Universitetu im. V.N. Karazina. Cepiâ Matematika, Prikladna Matematika i Mehanika, 2022
We consider a linear nonhomogeneous $m$-th order differential equation in a ring of formal power series with coefficients from some field of characteristic zero.
A. Goncharuk
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On the R-automorphisms of formal power series on several indeterminates and with coefficients over the ring R

Selecciones Matemáticas, 2022
In this paper, we show a way to characterize the R-automorphisms of formal power series on several indeterminates and with coefficients over a commutative ring with identity, R.
Soledad Ramírez C., Anderson Cárdenas F.   +1 more
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Weighted Logics for Nested Words and Algebraic Formal Power Series [PDF]

Logical Methods in Computer Science, 2010
Nested words, a model for recursive programs proposed by Alur and Madhusudan, have recently gained much interest. In this paper we introduce quantitative extensions and study nested word series which assign to nested words elements of a semiring. We show
Christian Mathissen
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INVESTIGATION OF STURM-LIOUVILLE PROBLEM SOLVABILITY IN THE PROCESS OF ASYMPTOTIC SERIES CREATION [PDF]

Научно-технический вестник информационных технологий, механики и оптики, 2015
Subject of Research. Creation of asymptotic expansions for solutions of partial differential equations with small parameter reduces, usually, to consequent solving of the Sturm-Liouville problems chain.
A. I. Popov
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Endo-Noetherian Skew Generalized Power Series Rings [PDF]

Assiut University Journal of Multidisciplinary Scientific Research, 2023
Endo-Noetherian modules were introduced by A. Kaidi and E. Sanchez] as a generalization of Noetherian modules. A left Ɍ-module M which satisfies the ascending chain condition for endomorphic kernels is said to be endo-Noetherian.
Ramy Abdel-Khaleq, Refaat Salem, Neamat Mohamed   +2 more
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New combinatorial computational methods arising from pseudo-singletons [PDF]

Discrete Mathematics & Theoretical Computer Science, 2008
Since singletons are the connected sets, the species $X$ of singletons can be considered as the combinatorial logarithm of the species $E(X)$ of finite sets.
Gilbert Labelle
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On composition of formal power series

International Journal of Mathematics and Mathematical Sciences, 2002
Given a formal power series g(x)=b0+b1x+b2x2+⋯ and a nonunit f(x)=a1x+a2x2+⋯, it is well known that the composition of g with f, g(f(x)), is a formal power series.
Xiao-Xiong Gan, Nathaniel Knox
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On the Cumulants of the First Passage Time of the Inhomogeneous Geometric Brownian Motion

Mathematics, 2021
We consider the problem of the first passage time T of an inhomogeneous geometric Brownian motion through a constant threshold, for which only limited results are available in the literature.
Elvira Di Nardo, Giuseppe D’Onofrio
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On formal power series over topological algebras

Extracta Mathematicae, 2022
We present a general survey on formal power series over topological algebras, along with some perspectives which are not easily found in the literature.
Martin Weigt, I. Zarakas
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