Timeline for What is the Cartan matrix for a dihedral group?
Current License: CC BY-SA 3.0
5 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Mar 21, 2017 at 15:58 | comment | added | David E Speyer | $\alpha_i^{\vee}(\alpha_i)$ is always $2$ under the conventions I'm used to. $d_i$ is the ratio between the proportional vectors $\alpha_i$ and $\alpha_i^{\vee}$ Probably best to read some standard book on Coxeter groups, e.g. Humphrey's, rather than me try to get it right. | |
| Mar 21, 2017 at 14:08 | vote | accept | Jianrong Li | ||
| Mar 21, 2017 at 14:07 | comment | added | Jianrong Li | thank you very much. $d_i =\sqrt{ \alpha_i^{\vee}(\alpha_i) }$ (the length of $\alpha_i$)?. | |
| Mar 21, 2017 at 13:52 | comment | added | David E Speyer | PS I prefer the notation $I_2^{(m)}$, so that the subscript is always the rank. | |
| Mar 21, 2017 at 13:44 | history | answered | David E Speyer | CC BY-SA 3.0 |