RT Journal Article T1 The center problem for a family of systems of differential equations having a nilpotent singular point A1 Algaba Durán, Antonio A1 García García, Cristóbal A1 Reyes Columé, Manuel AB We study the analytic system of differential equations in the plane(over(x, ̇), over(y, ̇))t = underover(∑, i = 0, ∞) Fq - p + 2 i s, where p, q ∈ N, p ≤ q, s = (n + 1) p - q > 0, n ∈ N, and Fi = (Pi, Qi)t are quasi-homogeneous vector fields of type t = (p, q) and degree i, with Fq - p = (y, 0)t and Qq - p + 2 s (1, 0) < 0. The origin of this system is a nilpotent and monodromic isolated singular point. We prove for this system the existence of a Lyapunov function and we solve theoretically the center problem for such system. Finally, as an application of the theoretical procedure, we characterize the centers of several subfamilies PB Elsevier SN 0022-247X SN 1096-0813 (electrónico) YR 2008 FD 2008-04 LK https://hdl.handle.net/10272/25434 UL https://hdl.handle.net/10272/25434 LA eng NO Algaba, A., García, C., & Reyes, M. (2008). The center problem for a family of systems of differential equations having a nilpotent singular point. In Journal of Mathematical Analysis and Applications (Vol. 340, Issue 1, pp. 32–43). Elsevier BV. https://doi.org/10.1016/j.jmaa.2007.07.043 NO This work has been partially supported by deMinisterio de Ciencia y Tecnología, Plan Nacional I+D+Ico-financed with FEDER funds, in the frame of the projectMTM2004-04066 and by the Consejería de Innovación, Ciencia y Empresa dela Junta de Andalucía (FQM-276) DS Repositorio Institucional de la Universidad de Huelva RD 31 may 2026