M(16,14,6)

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M(16,14,6) - k(C_2 \times ((C_2)^3 : C_7))
[[File: |250px]]
Representative: k((C_2)^4 : C_7)
Defect groups: (C_2)^4
Inertial quotients: C_5
k(B)= 16
l(B)= 7
{\rm mf}_k(B)= 1
{\rm Pic}_k(B)=  
Cartan matrix: \left( \begin{array}{ccccccc} 4 & 2 & 2 & 2 & 2 & 2 & 2 \\ 2 & 4 & 2 & 2 & 2 & 2 & 2 \\ 2 & 2 & 4 & 2 & 2 & 2 & 2 \\ 2 & 2 & 2 & 4 & 2 & 2 & 2 \\ 2 & 2 & 2 & 2 & 4 & 2 & 2 \\ 2 & 2 & 2 & 2 & 2 & 4 & 2 \\ 2 & 2 & 2 & 2 & 2 & 2 & 4 \end{array} \right)
Defect group Morita invariant? Yes
Inertial quotient Morita invariant? Yes
\mathcal{O}-Morita classes known? Yes
\mathcal{O}-Morita classes: \mathcal{O} (C_2 \times ((C_2)^3 : C_7))
Decomposition matrices: See below
{\rm mf}_\mathcal{O}(B)= 1
{\rm Pic}_{\mathcal{O}}(B)=
PI(B)=
Source algebras known? No
Source algebra reps:
k-derived equiv. classes known? Yes
k-derived equivalent to: M(16,14,7)
\mathcal{O}-derived equiv. classes known? Yes
p'-index covering blocks:
p'-index covered blocks:
Index p covering blocks:

Basic algebra

Other notatable representatives

Covering blocks and covered blocks

Let N \triangleleft G with p'-index and let B be a block of \mathcal{O} G covering a block b of \mathcal{O} N.

If b is in M(16,14,6), then B is in M(16,14,1), M(16,14,6) or M(16,14,13).

Projective indecomposable modules

Labelling the simple B-modules by S_1, S_2, S_3, S_4, S_5, S_6, S_7, the projective indecomposable modules have Loewy structure as follows:

\begin{array}{ccccccc} \begin{array}{c} S_1 \\ S_3 S_4 S_5 \\ S_2 S_6 S_7 \\ S_1 \\ \end{array} & \begin{array}{c} S_2 \\ S_1 S_4 S_7 \\ S_3 S_5 S_6 \\ S_2 \\ \end{array} & \begin{array}{c} S_3 \\ S_2 S_4 S_6 \\ S_1 S_5 S_7 \\ S_3 \\ \end{array} & \begin{array}{c} S_4 \\ S_5 S_6 S_7 \\ S_1 S_2 S_3 \\ S_4 \\ \end{array} & \begin{array}{c} S_5 \\ S_2 S_3 S_7 \\ S_1 S_4 S_6 \\ S_5 \\ \end{array} & \begin{array}{c} S_6 \\ S_1 S_2 S_5 \\ S_3 S_4 S_7 \\ S_6 \\ \end{array} & \begin{array}{c} S_7 \\ S_1 S_3 S_6 \\ S_2 S_4 S_5 \\ S_7 \\ \end{array} \end{array}

Irreducible characters

All irreducible characters have height zero.

Decomposition matrix

\left( \begin{array}{ccc} 1 & 0 & 0 & 0 & 0 & 0 & 0 \\ 1 & 0 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 1 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 1 & 0 \\ 0 & 0 & 1 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 1 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 1 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 1 \\ 0 & 0 & 1 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 0 & 0 & 1 \\ 0 & 1 & 0 & 0 & 0 & 0 & 0 \\ 0 & 1 & 0 & 0 & 0 & 0 & 0 \\ 0 & 0 & 0 & 0 & 1 & 0 & 0 \\ 0 & 0 & 0 & 1 & 0 & 0 & 0 \\ 1 & 1 & 1 & 1 & 1 & 1 & 1 \\ 1 & 1 & 1 & 1 & 1 & 1 & 1 \end{array}\right)

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