A Generalization of Tutte's Characterization of Totally Unimodular Matrices

  title={A Generalization of Tutte's Characterization of Totally Unimodular Matrices},
  author={James F. Geelen},
  journal={J. Comb. Theory, Ser. B},
  • J. Geelen
  • Published 1 May 1997
  • Mathematics
  • J. Comb. Theory, Ser. B
We characterize the symmetric (0, 1)-matrices that can be signed symmetrically so that every principal submatrix has determinant 0, ±1. This characterization generalizes Tutte's famous characterization of totally unimodular matrices. The result can be viewed as an excluded minor theorem for an interesting class of delta-matroids. 

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