In his e-mail message of 1993/02/26, Bruce Kaskel writes:
Could someone possibly tell me what I am doing wrong here?
gap> s4 := SymmmetricGroup( 4 );; gap> cc := ConjugacyClassesSubgroups( s4 );; gap> cc2 := cc;; gap> r := Representative( cc2 );; gap> g := Group( r ); Group( (3,4) ) gap> 2syl := SylowSubgroup( g, 2 ); Error, Record: element 'orbit' must have an assigned value at ...
This is a bug in GAP 3.1 (patchlevel 0). It is fixed in the first
upgrade to V3R1P1 and in GAP 3.2. The problem was that
'PermGroupOps.SylowSubgroup' assumed that once the size of a permutation
group is known (and it is known for 'g', since it was known for 'r'),
also a stabilizer chain is known (but 'g' has no stabilizer chain,
because this is not copied by 'Group').
-- .- .-. - .. -. .-.. --- ...- . ... .- -. -. .. -.- .- Martin Sch"onert, Martin.Schoenert@Math.RWTH-Aachen.DE, +49 241 804551 Lehrstuhl D f"ur Mathematik, Templergraben 64, RWTH, D 51 Aachen, Germany