NON-TRUNCATED FORMAL SERIES SYMMETRIES AND GENERALIZED VIRASORO ALGEBRA - AKNS-TYPE BREAKING SOLITON EQUATION

Using the formal series symmetry approach, we obtain three sets of gen eralized symmetries of the AKNS-type breaking soliton equation. These sets of formal series symmetries are not truncated except that the arb itrary functions of the formal series symmetries are fixed as polynomi als of the corresponding independent variables. Differing from the tru ncated cases such as KP and Toda field equations, these non-truncated symmetries constitute another type of generalization of the Virasoro a lgebra.