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Timeline for does this group have a name?

Current License: CC BY-SA 2.5

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Mar 23, 2011 at 2:42 comment added Steve D The normal closure of $c$ is infinite.
Dec 3, 2010 at 3:09 vote accept dan
Dec 3, 2010 at 1:38 comment added Denis Osin It is not quite clear for me why $c$ commutes with all conjugates by $b^n$.
Dec 3, 2010 at 1:26 history edited Denis Osin CC BY-SA 2.5
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Dec 3, 2010 at 1:21 comment added user6976 It looks like the group is virtually cyclic. In fact it is an extension of the 4-element Klein group by the infinite cyclic group that permutes the two generating involutions. Do a change of variables $c=ba$. Get $c^2=1$, $c$ commutes with all conjugates by $b^n$. So the group is a factor-group of the lamplighter group. Now the relation $a^2b=ba^2$ means, if I am not mistaken, $cbcb=bcbc$. Which means $cc^b=c^bc^{b^2}$ or $c=c^{b^2}$. So the normal subgroup generated by $c$ is of order 4. Right?
Dec 3, 2010 at 1:15 history answered Denis Osin CC BY-SA 2.5