> < ^ Date: Mon, 10 Aug 1992 17:53:42 +0200
> < ^ From: David Sibley <sibley@math.psu.edu >
> ^ Subject: Permutation groups from Ag groups

How do I make a permutation group from an Ag group? Specifically,
I would like to get the action on the cosets of a subgroup. The
following is a summary of what I tried, but it doesn't work.

(BTW, is this forum broken? I have not received any messages in
it for over a month.)

David Sibley
gap> a:=TwoGroup(256,3678);;
gap> b:=Subgroup(a,[a.1^2,a.2^2,a.3^2]);;
gap> g:=Operation(a,Cosets(a,b),OnRightCosets);;
Error, for: <list> must evaluate to a list at
for <var> in set ... in
opr( D[i], gen ) called from
arg[1].operations.Operation( arg[1], arg[2], arg[3] ) called from
Operation( a, Cosets( a, b ), OnRightCosets ) called from
main loop
brk> quit;
gap> g:=OperationCosetsFpGroup(a,b);;
Error, Record: element 'relators' must have an assigned value at
if gen ^ 2 in G.relators or gen ^ (-1 * 2) in G.relators ... in
CosetTableFpGroup( G, H ) called from
OperationCosetsFpGroup( a, b ) called from
main loop
brk> quit;

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