Algebraic periodic points of transcendental entire functions

We prove the existence of transcendental entire functions $f$ having a property studied by Mahler, namely that $f(\bar{\mathbb{Q}})\subseteq \bar{\mathbb{Q}}$ and $f^{-1}(\bar{\mathbb{Q}})\subseteq \bar{\mathbb{Q}}$, and in addition having a prescribed number of $k$-periodic algebraic orbits, for all $k\ge 1$. Under a suitable topology, such functions are shown to be dense in the set of all entire transcendental functions.