Binary Supersolvable Matroids and Modular Constructions

نویسندگان

  • GÜNTER M. ZIEGLER
  • Thomas H. Brylawski
  • G. M. ZIEGLER
چکیده

Let Jt be the class of binary matroids without a Fano plane as a submatroid. We show that every supersolvable matroid in JÍ is graphic, corresponding to a chordal graph. Then we characterize the case that the modular join of two matroids is supersolvable. This is used to study modular flats and modular joins of binary supersolvable matroids. We decompose supersolvable matroids in JH as modular joins with respect to hyperplanes. For such matroids every modular flat is contained in a maximal chain of modular flats, and thus modular joins are again supersolvable.

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تاریخ انتشار 1991