We investigate the convergence of the rows (fixed denominator degree) of the Walsh array of best rational approximants to a meromorphic function. We give an explicit algorithm for determining when convergence is guaranteed and obtain rates of convergence.in the appropriate cases. This algorithm also provides the solution to an integer programming problem that arises in the study of Pade approxi...

in this paper, we give an analytical approximate solution for an integro- differential equation which describes the charged particle motion for certain configurations of oscillating magnetic fields is considered. the homotopy analysis method (ham) is used for solving this equation. several examples are given to reconfirm the efficiency of these algorithms. the results of applying this procedure...

in this study, a new efficient semi-analytical method is introduced to give approximate solutions of strongly nonlinear oscillators. the proposed method is based on combination of two different methods, the multi-step homotopy analysis method and spectral method, called the multi-step spectral homotopy analysis method (msham). in this method, firstly, we propose a new spectral homotopy analysis...

We construct compatible symplectic structures on manifolds Q3 × S1 for Waldhausen Q3 and show it is possible iff Q3 is a Stallings fibrations over S1. We describe bordisms of Lagrangian T 2-bundles over S1 × I .

We propose a notion of groupoid homotopy for generalized maps. This notion of groupoid homotopy generalizes the notions of natural transformation and strict homotopy for functors. The groupoid homotopy type of a Lie groupoid is shown to be invariant under Morita equivalence. As an application we consider orbifolds as groupoids and study the orbifold homotopy between orbifold maps induced by the...