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Extensions of line-closed combinatorial geometries

✍ Scribed by Mark D. Halsey

Publisher: Elsevier Science
Year: 1990
Tongue: English
Weight: 253 KB
Volume: 82
Category: Article
ISSN: 0012-365X
DOI: 10.1016/0012-365x(90)90203-t

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✦ Synopsis

In [4], line-closed combinatorial geometries were studied. Here, given a line-closed combinatorial geometry G(X), we determine all single point extensions of G(X) that are line-closed. Further, if H(X U r) is a line-closed geometry that is a smooth extension of G(X) we give a natural necessary and sufficient condition for every geometry between G and H to be line-closed.

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