Séminaire Lotharingien de Combinatoire, B14f (1986), 8 pp.
[Formerly: Publ. I.R.M.A. Strasbourg, 1986, 323/S-14, p.
81-88.]
Gareth Jones
Enumerating Regular Maps and Normal Subgroups of the Modular Group
Abstract.
The icosahedron is a regular orientable triangular map with rotation
group isomorphic to PSL2(q) for q = 4 and
q = 5 . We shall consider, for each finite group G, the
number NG of
regular orientable triangular (= r.o.t.) maps with
orientation-preserving automorphism group G. The method used is quite
general, though here we will concentrate
on the groups G = PSL2(q); thus we are
enumerating the `q-analogues'
of the icosahedron.
The following version is available: