Speaker:  Stephen Lacina, Truman State University

Title:  Posets that are CC-shellable but are not CL-shellable

Abstract:

We present two perhaps surprisingly small posets, one graded and one non-graded, that are CC-shellable in the sense of Kozlov but not CL-shellable in the sense of Björner and Wachs. In the spirit of Björner and Wachs’ Recursive Atom Orders (RAO) and Hersh and Stadnyk’s Generalized Recursive Atom Orders (GRAO), we also introduce two recursive techniques for proving that a bounded poset is shellable, one of which is equivalent to CC-shellability.

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