PreprintSolvable normal subgroups of 2knot groupsJ.A.HillmanAbstractIf the fundamental group of an orientable, strongly minimal PD4complex has one end then it has no nontrivial locallyfinite normal subgroup. Hence if a 2knot group is virtually solvable then either it has two ends or is the group of Fox's Example 10, or is torsionfree and polycyclic of Hirsch length 4. If the centre of a 2knot group \(G\) is nontrivial then either \(G\) has two ends, or \(G\) has one end and the centre is torsionfree, or \(G\) has infinitely many ends and the centre is finite. The Hirsch–Plotkin radical of any 2knot group is nilpotent. Keywords: centre, HirschPlotkin radical, solvable, 2knot.AMS Subject Classification: Primary 57Q45.
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