  Defining a computational basis of pseudo-number states, we interpret a
coherent state of large amplitude, $|\alpha|\gg\frac{d}{2\pi}$, as a qudit ---
a $d$-level quantum system --- in a state that is an even superposition of $d$
pseudo-number states. A pair of such coherent-state qudits can be prepared in
maximally entangled state by generalized Controlled-$Z$ operation that is based
on cross-Kerr nonlinearity, which can be weak for large $d$. Hence, a
coherent-state optical qudit cluster state can be prepared by repetitive
application of the generalized Controlled-$Z$ operation to a set of coherent
states. We thus propose an optical qudit teleportation as a simple
demonstration of cluster state quantum computation.
