Bases of cocycle lattices and submatrices of a Hadamard matrix

نویسندگان

  • Winfried Hochstättler
  • Martin Loebl
چکیده

We study the lattice lat(M) of cocycles of a binary matroid M. By an isomorphism we show that such lattices are equivalent to lattices generated by the columns of proper submatrices of Sylvester matrices of full row length. As an application we show that the cocycle lattice of a recursively deened class of matroids, including all binary matroids of rank four, always has a basis consisting of cocycles.

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تاریخ انتشار 1997