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Counterexamples to the Neggers-Stanley conjecture
Author(s):
Petter
Brändén
Journal:
Electron. Res. Announc. Amer. Math. Soc.
10
(2004),
155 - 158.
MSC (2000):
Primary 06A07, 26C10
Posted:
December 24, 2004
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Abstract:
The Neggers-Stanley conjecture asserts that the polynomial counting the linear extensions of a labeled finite partially ordered set by the number of descents has real zeros only. We provide counterexamples to this conjecture.
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Additional Information:
Petter
Brändén
Affiliation:
Department of Mathematics, Chalmers University of Technology and Göteborg University, S-412~96 Göteborg, Sweden
Email:
branden@math.chalmers.se
DOI:
10.1090/S1079-6762-04-00140-4
PII:
S 1079-6762(04)00140-4
Keywords:
Neggers-Stanley conjecture,
partially ordered set,
linear extension,
real roots
Received by editor(s):
August 31, 2004
Posted:
December 24, 2004
Communicated by:
Sergey Fomin
Copyright of article:
Copyright
2004,
American Mathematical Society
The copyright for this article reverts to public domain after 28 years from publication.
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