M(8,5,8)

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M(8,5,8) - [math]B_0(k(\rm Aut (SL_2(8)))[/math]
M(8,5,8)quiver.png
Representative: [math]B_0(k(\rm Aut (SL_2(8)))[/math]
Defect groups: [math]C_2 \times C_2 \times C_2[/math]
Inertial quotients: [math]C_7:C_3[/math]
[math]k(B)=[/math] 8
[math]l(B)=[/math] 5
[math]{\rm mf}_k(B)=[/math] 1
[math]{\rm Pic}_k(B)=[/math]  
Cartan matrix: [math]\left( \begin{array}{ccccccc} 4 & 2 & 2 & 4 & 2 \\ 2 & 4 & 2 & 4 & 2 \\ 2 & 2 & 4 & 4 & 2 \\ 4 & 4 & 4 & 8 & 3 \\ 2 & 2 & 2 & 3 & 2 \\ \end{array} \right)[/math]
Defect group Morita invariant? Yes
Inertial quotient Morita invariant? Yes
[math]\mathcal{O}[/math]-Morita classes known? Yes
[math]\mathcal{O}[/math]-Morita classes: [math]B_0(\mathcal{O}(\rm Aut (SL_2(8)))[/math]
Decomposition matrices: [math]\left( \begin{array}{ccccc} 1 & 0 & 0 & 0 & 0 \\ 0 & 1 & 0 & 0 & 0 \\ 0 & 0 & 1 & 0 & 0 \\ 1 & 0 & 0 & 1 & 0 \\ 0 & 1 & 0 & 1 & 0 \\ 0 & 0 & 1 & 1 & 0 \\ 1 & 1 & 1 & 1 & 1 \\ 1 & 1 & 1 & 2 & 1 \\ \end{array}\right)[/math]
[math]{\rm mf}_\mathcal{O}(B)=[/math] 1
[math]{\rm Pic}_{\mathcal{O}}(B)=[/math]
[math]PI(B)=[/math] {{{PIgroup}}}
Source algebras known? No
Source algebra reps:
[math]k[/math]-derived equiv. classes known? Yes
[math]k[/math]-derived equivalent to: M(8,5,6), M(8,5,7)
[math]\mathcal{O}[/math]-derived equiv. classes known? Yes
[math]p'[/math]-index covering blocks:
[math]p'[/math]-index covered blocks:
Index [math]p[/math] covering blocks: {{{pcoveringblocks}}}

Basic algebra

Quiver: a:<4,1>, b:<1,4>, c:<2,4>, d:<4,2>, e:<4,3>, f:<3,4>, g:<4,5>, h:<5,4>

Relations w.r.t. [math]k[/math]:

Other notatable representatives

Projective indecomposable modules

Labelling the simple [math]B[/math]-modules by [math]1,2,3,4,5[/math], the projective indecomposable modules have Loewy structure as follows:

[math]\begin{array}{ccccc} \begin{array}{c} 1 \\ 4 \\ 1 \ 2 \ 3 \ 5 \\ 4 \ 4 \\ 1 \ 2 \ 3 \ 5 \\ 4 \\ 1 \\ \end{array}, & \begin{array}{c} 2 \\ 4 \\ 1 \ 2 \ 3 \ 5 \\ 4 \ 4 \\ 1 \ 2 \ 3 \ 5 \\ 4 \\ 2 \\ \end{array}, & \begin{array}{c} 3 \\ 4 \\ 1 \ 2 \ 3 \ 5 \\ 4 \ 4 \\ 1 \ 2 \ 3 \ 5 \\ 4 \\ 3 \\ \end{array}, & \begin{array}{c} 4 \\ 1 \ 2 \ 3 \ 5 \\ 4 \ 4 \ 4 \\ 1 \ 1 \ 2 \ 2 \ 3 \ 3 \ 5 \\ 4 \ 4 \ 4 \\ 1 \ 2 \ 3 \ 5 \\ 4 \\ \end{array}, & \begin{array}{c} 5 \\ 4 \\ 1 \ 2 \ 3 \\ 4 \\ 1 \ 2 \ 3 \\ 4 \\ 5 \\ \end{array} \end{array} [/math]

Irreducible characters

All irreducible characters have height zero.

Back to [math]C_2 \times C_2 \times C_2[/math]