most recent 30 from http://mathoverflow.net 2013-05-24T03:03:05Z http://mathoverflow.net/feeds/user/15977 http://www.creativecommons.org/licenses/by-nc/2.5/rdf http://mathoverflow.net/questions/68639/algebra-counterexample-request-linear-quotients/68724#68724 Aldo Conca 2011-06-24T11:21:27Z 2011-06-24T11:21:27Z

<p>If you take square-free monomials ideals and consider the Alexander duality, then linear resolution is dual to Cohen-Macaulay and linear quotient is dual to shellable. Hence you are looking for a non-shellable simplicial complex that is CM in all the characteristic. </p> <p>Volkmar Welker mentioned to me that the EG models web page (http://www.eg-models.de/) lists many examples of simplicial complexes with unusual or difficult to find proprieties. There you find what you are looking for. For example, EG Model No. 2003.05.003 is a nonshellable but constructible 2-dimensional simplicial complex. </p>