Quotients of tangential -blocks

Author:
Geoffrey Whittle

Journal:
Proc. Amer. Math. Soc. **102** (1988), 1088-1098

MSC:
Primary 05B35

DOI:
https://doi.org/10.1090/S0002-9939-1988-0934895-4

MathSciNet review:
934895

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Abstract: A tangential -block over is a simple matroid representaba over with critical exponent for which every proper loopless minor has critical exponent at most . Such matroids are of central importance in the critical problem of Crapo and Rota. In this paper we provide sufficient conditions for a quotient of a tangential -block over to be also a tangential -block over . This enables us to show that there exist rank supersolvable tangential -blocks over exactly when .

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DOI:
https://doi.org/10.1090/S0002-9939-1988-0934895-4

Article copyright:
© Copyright 1988
American Mathematical Society