GAP 4.8.9 installation with standard packages -- copy to your CoCalc project to get it
#Example: "3gp-PG-x-i" . . . based on example from Werner
#Iterated descendants example
#vars: F, procId;
#options: OutputLevel
F := FreeGroup("a", "b");
procId := PqStart(F : Prime := 3);
#comment: set a different print level by supplying <OutputLevel>
PqPcPresentation(procId : ClassBound := 1,
#sub <OutputLevel> for <1> if set and ok
OutputLevel := 1);;
PqComputePCover(procId);;
PqPGSupplyAutomorphisms(procId, [ [[1,1],
[0,1]],
[[0,1],
[1,0]] ]);;
PqPGExtendAutomorphisms(procId);;
PqPGConstructDescendants(procId : ClassBound := 2,
CapableDescendants,
BasicAlgorithm);
PqPGSetDescendantToPcp(procId, 2, 5);
PqPGExtendAutomorphisms(procId);;
PqPGConstructDescendants(procId : ClassBound := 3,
CapableDescendants,
BasicAlgorithm);
PqPGSetDescendantToPcp(procId, 3, 2);
PqPGExtendAutomorphisms(procId);;
PqPGConstructDescendants(procId : ClassBound := 4,
CapableDescendants,
BasicAlgorithm);
PqPGSetDescendantToPcp(procId, 4, 2);
PqPGExtendAutomorphisms(procId);;
PqPGConstructDescendants(procId : ClassBound := 5,
CapableDescendants,
BasicAlgorithm);
PqPGSetDescendantToPcp(procId, 5, 1);
PqPGExtendAutomorphisms(procId);;
PqPGConstructDescendants(procId : ClassBound := 6,
CapableDescendants,
BasicAlgorithm);
PqPGSetDescendantToPcp(procId, 6, 1);
PqPGExtendAutomorphisms(procId);;
PqPGConstructDescendants(procId : ClassBound := 7,
CapableDescendants,
BasicAlgorithm);
PqPGSetDescendantToPcp(procId, 7, 1);
PqPGExtendAutomorphisms(procId);;
PqPGConstructDescendants(procId : ClassBound := 8,
CapableDescendants,
BasicAlgorithm);