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UID:20260602T074727EDT-4065GWbI5u@132.216.98.100
DTSTAMP:20260602T114727Z
DESCRIPTION:Title: Whitehead Graphs and Irreducible Half-clean HNN Extensio
 ns\n\n\n	Abstract: We would describe given an irreducible half-clean HNN ex
 tension $H$ of a finitely generated free group\, how we can construct an a
 scending irreducible half-clean HNN extension $G$ such that $H$ is a subgr
 oup of $G$. We first introduce the Whitehead automorphisms on free groups\
 , followed by stating Stalling's theorem (1996) on Whitehead graphs. Then\
 , we describe how to construct $G$ by Stalling's theorem.\n
DTSTART:20230215T200000Z
DTEND:20230215T210000Z
LOCATION:Room 920\, Burnside Hall\, CA\, QC\, Montreal\, H3A 0B9\, 805 rue 
 Sherbrooke Ouest
SUMMARY:William Chong  (91ºÚÁÏÍø)
URL:/mathstat/channels/event/william-chong-mcgill-univ
 ersity-346113
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