  The characterization of genuine multiparticle entanglement is important for
entanglement theory as well as experimental studies related to quantum
information theory. Here, we completely characterize genuine multiparticle
entanglement for four-qubit states diagonal in the cluster-state basis. In
addition, we give a complete characterization of multiparticle entanglement for
all five-qubit graph states mixed with white noise, for states diagonal in the
basis corresponding to the five-qubit Y-shaped graph, and for a family of graph
states with an arbitrary number of qubits.
