TITLE: Numerical integration of high-order variational equations of ODEs AUTHORS: Joan Gimeno^(1), Angel Jorba^(1), Marc Jorba-Cusco^(2), Narcis Miguel^(3) and Maorong Zou^(4) (1) Departament de Matematiques i Informatica Universitat de Barcelona, Gran Via 585, 08007 Barcelona, Spain (2) Universidad Internacional de la Rioja (UNIR), Av. de la Paz, 137, 26006 Logro\~{n}o, Spain (3) PAL Robotics S.L., Carrer de Pujades, 77, 4-4, 08005 Barcelona, Spain (4) Department of Mathematics, University of Texas at Austin, Austin, TX 78712, USA E-mails: joan@maia.ub.es, angel@maia.ub.es, marc.jorba@unir.net, narcis.miguel@pal-robotics.com, mzou@math.utexas.edu ABSTRACT: This paper discusses the numerical integration of high-order variational equations of ODEs. It is proved that, given a numerical method (say, any Runge-Kutta or Taylor method), to use automatic differentiation on this method (that is, using jet transport up to order $p$ with a time step $h$ for the numerical integration) produces exactly the same results as integrating the variational equations up to of order $p$ with the same method and time step $h$ as before. Finally, the paper discusses how to use jet transport to obtain power expansions of Poincar\'e maps (either with spatial or temporal Poincar\'e sections) and invariant manifolds. Some examples are provided.