This work studies a variety of factorizations for the radial isotropic
oscillator Hamiltonian leading to a hierarchy of radial Hamiltonians
labeled by a discrete index. These results are applied to find a relat
ionship between the ladder operators (which allow one to move in the e
igenfunction space of a fixed Hamiltonian) and shift operators (that c
onnect eigenfunctions of different Hamiltonians inside the factorizati
on hierarchy). The operators appearing in the factorizations span a dy
namical algebra whose action is schematically drawn on a two-dimension
al lattice. Afterwards it is shown in detail that the relevant subalge
bra is isomorphic to an extended (1 + 2) Newton-Hooke conformal algebr
a corresponding to a two-dimensional wave equation. As a byproduct; fo
r each element of the hierarchy there is derived a new one-parametric
continuous family of almost-isospectral radial Hamiltonians. (C) 1996
Academic Press, Inc.