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JOURNAL OF
ALGEBRAIC
COMBINATORICS

  Editors-in-chief: C. A. Athanasiadis, T. Lam, A. Munemasa, H. Van Maldeghem
ISSN 0925-9899 (print) • ISSN 1572-9192 (electronic)
 

Unimodular Triangulations and Coverings of Configurations Arising from Root Systems

Hidefumi Ohsugi and Takayuki Hibi

DOI: 10.1023/A:1012772002661

Abstract

Existence of a regular unimodular triangulation of the configuration F + È{ (0,0,...,0)} \text in R n Φ^ + \cup \{ (0,0,...,0)\} {\text{ in }}R^n , where F Ì R n Φ\subset R^n and where (0, 0,...,0 ) is the origin of R n R^n , will be shown for PHgr = B n , C n , D n and BC n . Moreover, existence of a unimodular covering of a certain subconfiguration of the configuration A n+1 + will be studied.

Pages: 199–219

Keywords: initial ideals; unimodular triangulations; unimodular coverings; root systems; positive roots

Full Text: PDF

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