A reducible representation of the Temperley-Lieb algebra is constructed on
the tensor product of n-dimensional spaces. One obtains as a centraliser of
this action a quantum algebra (a quasi-triangular Hopf algebra) U_q with a
representation ring equivalent to the representation ring of the sl_2 Lie
algebra. This algebra U_q is the symmetry algebra of the corresponding open
spin chain.Comment: 14 pages LaTex; typos corrected and two references adde