  We have introduced a class of exactly soluble Hamiltonian with either
SO(2n+1) or SU(2) symmetry, whose ground states are the SO(2n+1) symmetric
matrix product states. The hidden topological order in these states can be
fully identified and characterized by a set of nonlocal string order
parameters. The Hamiltonian possesses a hidden $(Z_{2}\times Z_{2})^{n} $
topological symmetry. The breaking of this hidden symmetry leads to $4^{n}$
degenerate ground states with disentangled edge states in an open chain system.
Such matrix product states can be regarded as cluster states, applicable to
measurement-based quantum computation.
