H-TREES, RESTRICTIONS OF DOWLING GROUP GEOMETRIES
نویسندگان
چکیده
منابع مشابه
Dowling group geometries and the critical problem
This paper relates the critical problem of Crapo and Rota [ " On the Foundations of Combinatorial Theory: Combinatorial Geometries, " M.I.T. Press, Cambridge, MA, 19703 to Dowling group geometries. If A is a finite group, Q,(A) is the rank-r Dowling group geometry over A, and M is a rank-r matroid embeddable as a minor of Q,(A), then it is shown that the critical exponent of M over A is well de...
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Given a finite group G and a natural number n, we study the structure of the complex of nested sets of the associated Dowling lattice Qn(G) (Proc. Internat. Sympos., 1971, pp. 101–115) and of its subposet of the G-symmetric partitions Qn(G) which was recently introduced by Hultman (http://www.math.kth.se/ ~hultman/, 2006), together with the complex of G-symmetric phylogenetic trees T G n . Hult...
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ژورنال
عنوان ژورنال: Bulletin of the Korean Mathematical Society
سال: 2015
ISSN: 1015-8634
DOI: 10.4134/bkms.2015.52.3.955