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On the Action of the Sporadic Simple Baby Monster Group on its Conjugacy Class 2B

Published online by Cambridge University Press:  01 February 2010

Jürgen Müller
Affiliation:
Lehrstuhl D für Mathematik, RWTH Aachen, Templergraben 64, D-52062 Aachen, Germany, Juergen.Mueller@math.rwth-aachen.de

Abstract

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We determine the character table of the endomorphism ring of the permutation module associated with the multiplicity-free action of the sporadic simple Baby Monster group B on its conjugacy class 2B, where the centraliser of a 2B-element is a maximal subgroup of shape 21+22.Co2. This is one of the first applications of a new general computational technique to enumerate big orbits.

Type
Research Article
Copyright
Copyright © London Mathematical Society 2008

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