A remark on stable subharmonic solutions of time-periodic reaction–diffusion equations

This paper is concerned with a time-periodic reaction–diffusion equation. It is known that typical trajectories approach periodic solutions with possibly longer period than that of the equation. Such solutions are called subharmonic solutions. In this paper, for any domain Ω, time-period τ >0 and integer n 2, we construct an example of a time-periodic reaction–diffusion equation on Ω with a minimal period τ which possesses a stable solution of minimal period nτ.  2003 Elsevier Inc. All rights reserved