Electronic Journal of Differential Equations,
Vol. 2010(2010), No. 72, pp. 1-12.

Title: Almost periodic solutions of higher order differential equations
       on Hilbert spaces
       
Author: Lan Thanh Nguyen (Western Kentucky Univ., Bowling Green, KY, USA)

Abstract:
 We find necessary and sufficient conditions for the differential
 equation
 $$
 u^{(n)}(t) = Au(t)+f(t), \quad t\in \mathbb{R}
 $$
 to have a unique almost periodic solution. Some applications are
 also given.

Submitted March 26, 2010. Published May 17, 2010.
Math Subject Classifications: 34G10, 34K06, 47D06.
Key Words: Almost periodic; higher order differential equations