Timeline for $Aut(\mathbb{Z}G)=?$ for $G=\mathbb{Z}^2\rtimes_n\mathbb{Z}$
Current License: CC BY-SA 3.0
4 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Nov 27, 2013 at 3:31 | vote | accept | Jiang | ||
| Nov 13, 2013 at 14:43 | comment | added | YCor | It would be useful to describe the automorphism group of $G_n$ at the first place. This group lies in an extension $1\to\mathbf{Z}^2\to\mathrm{Aut}(G_n)\to\mathrm{GL}_2(\mathbf{Z})\to 1$. The right map is the action on the quotient by the central and characteristic subgroup $\langle z\rangle$. The kernel $\mathbf{Z}^2$ is an overgroup of index $n$ of the group of inner automorphisms: these are the automorphisms $(x,y,z)\mapsto (xz^a,yz^b,z)$ for $(a,b)\in\mathbf{Z}$. | |
| Nov 13, 2013 at 4:32 | answer | added | Mariano Suárez-Álvarez | timeline score: 2 | |
| Nov 13, 2013 at 3:46 | history | asked | Jiang | CC BY-SA 3.0 |