Before revision:  We show that for this model with cooperative interaction all conformations with minimal energy are combinations of lattice models of alpha-helix and beta-strand. We show that for lattice polymers of the length not longer that 38 monomers we can describe all conformations with minimal energy.
After revision:  We show that for this model with cooperative interaction all conformations with minimal energy are combinations of lattice models of alpha--helix and beta--strand. Moreover for lattice polymers of the length not longer that 38 monomers we can describe all conformations with minimal energy.