Séminaire Lotharingien de Combinatoire, B21r (1989), 6 pp.
[Formerly: Publ. I.R.M.A. Strasbourg, 1990, 413/S-21, p.
141-146.]
Volkmar Welker
Über die Möbiuszahl des Verbands der Untergruppe einer endlichen auflösbaren Gruppe
Abstract.
As is well-known, the set of subgroups of a group G forms a lattice,
which we denote by Λ(G) in the sequel. For a finite solvable
group G, we describe a path to determine the Möbius number μ(Λ(G))
from the exact knowledge of the principal factors of G. The formula that
we find for μ(Λ(G)) must be considered as a more precise version of a
formula due to Kratzer and Thévenez, the latter being a simple corollary of our formula.
The following version is available: