Quandles constructed from finite groups are finite

This commit is contained in:
Glen Whitney 2017-10-21 20:47:54 +02:00
parent 35301b4839
commit ae71d58873

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@ -76,7 +76,7 @@ InstallOtherMethod(LeftQuotient, "for two conjugator objects",
InstallMethod(ConjugationQuandle, "for a group",
[IsGroup and IsFinite],
function(G)
local fam, elts;
local fam, elts, Q;
fam := CollectionsFamily(ConjugatorFamily(ElementsFamily(FamilyObj(G))));
# Question: how do we easily/quickly determine a set of generators of
# Conj(G) from a set of generators of G, so that we can handle infinite
@ -85,7 +85,11 @@ InstallMethod(ConjugationQuandle, "for a group",
# What we would like to do is
# return AsLeftQuandle[NC?](elts);
# but that's NIY.
return LeftQuandleNC(fam, elts);
Q := LeftQuandleNC(fam, elts);
# We know that elts was actually closed under * and LeftQuotient, and
# since we are in a method only for finite groups, ergo Q is finite:
SetIsFinite(Q, true);
return Q;
end);