27 citations · 84 across the 34 of their papers we have counts for
10 papers · 2 filters
Exponential asymptotics, transseries, and generalized Borel summation for analytic rank one systems of ODE's
O. Costin
For analytic nonlinear systems of ordinary differential equations, under some non-degeneracy and integrability conditions we prove that the formal exponential series solutions (tra…
Rigorous WKB for finite order linear recurrence relations with smooth coefficients
O. Costin, R. D. Costin
We study the behavior of recurrence relations of the type $k\in \zdd$ ( fixed). The are functions in each variable…
Optimal uniform estimates and rigorous asymptotics beyond all orders for a class of ODE's
O. Costin, M. D. Kruskal
For first order differential equations of the form and second order homogeneous linear differential equations with locally integrab…
On Borel summation and Stokes phenomena of nonlinear differential systems
O. Costin
In this paper we study analytic (linear or) nonlinear systems of ordinary differential equations, at an irregular singularity of rank one, under nonresonance conditions. It is show…
Movable singularities of solutions of difference equations in relation to solvability and a study of a superstable fixed point
O. Costin, M. D. Kruskal
A unique analytic continuation result is proven for solutions of a relatively general class of difference equations by using techniques of generalized Borel summability. We overvie…
Rigorous bounds of Stokes constants for some nonlinear ODEs at rank one irregular singularities
O. Costin, R. D. Costin, M. Kohut
A rigorous way to obtain sharp bounds for Stokes constants is introduced and illustrated on a concrete problem arising in applications.