Finding low-energy homopolymer conformations by a discrete approach C. Lavor, 1 A. Mucherino, 2 L. Liberti, 3 N. Maculan 4 1 IMECC-UNICAMP, Campinas-SP, Brazil, clavor@ime.unicamp.br 2 IRISA, University of Rennes 1, Rennes, France, antonio.mucherino@irisa.fr 3 LIX, École Poleytechnique, Palaiseau, France, liberti@lix.polytechnique.fr 4 COPPE, Federal University of Rio de Janeiro, Rio de Janeiro-RJ, Brazil, maculan@cos.ufrj.br 1. Introduction