  A class of truncated tight-binding Hermitian and non-Hermitian lattices with
commensurate energy levels, showing periodic reconstruction of the wave packet,
is presented. Examples include exact Bloch oscillations on a finite lattice,
periodic wave packet dynamics in non-Hermtian lattices with a complex linear
site-energy gradient, and self-imaging in lattices with commensurate energy
levels quadratically-varying with the quantum number.
