Über Anzahlmatrizen von Quaternionenordnungen und quadratischen Formen.
Binary quadratic residue codes of length produce via construction and density doubling type II lattices like the Leech. Recently, quaternary quadratic residue codes have been shown to produce the same lattices by construction modulo . We prove in a direct way the equivalence of these two constructions for . In dimension 32, we obtain an extremal lattice of type II not isometric to the Barnes-Wall lattice . The equivalence between construction modulo plus density doubling and construction...