A shellable poset that is not lexicographically shellable

Abstract

It is known that a lexicographically shellable poset is shellable, and it has been asked whether the two concepts are equivalent. We provide a counterexample, a shellable graded poset that is not lexicographically shellable.

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Vince, A., Wachs, M. A shellable poset that is not lexicographically shellable. Combinatorica 5, 257–260 (1985). https://doi.org/10.1007/BF02579370

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AMS subject classification (1980)

  • 05 C 65
  • 06 A 10