On the Excluded Minors for Quaternary Matroids
نویسندگان
چکیده
This paper strengthens the excluded-minor characterization of GF(4)-representable matroids. In particular, it is shown that there are only finitely many 3-connected matroids that are not GF(4)-representable and that have no U2, 6 -, U4, 6 -, P6 -, F & 7 -, or (F & 7 )*-minors. Explicitly, these matroids are all minors of S(5, 6, 12) with rank and corank at least 4, and P"8 , the matroid that can be obtained from S(5, 6, 12) by deleting two elements, contracting two elements, and then relaxing the only pair of disjoint circuit-hyperplanes. 2000 Academic Press
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ورودعنوان ژورنال:
- J. Comb. Theory, Ser. B
دوره 80 شماره
صفحات -
تاریخ انتشار 2000