Difference between revisions of "M(16,14,6)"

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(Removed incorrect Lloewy series)
 
Line 4: Line 4:
 
|representative =  <math>k((C_2)^4 : C_7)</math>
 
|representative =  <math>k((C_2)^4 : C_7)</math>
 
|defect = [[(C2)%5E4|<math>(C_2)^4</math>]]
 
|defect = [[(C2)%5E4|<math>(C_2)^4</math>]]
|inertialquotients = <math>C_5</math>
+
|inertialquotients = <math>C_7</math>
 
|k(B) = 16
 
|k(B) = 16
 
|l(B) = 7
 
|l(B) = 7
Line 48: Line 48:
 
== Projective indecomposable modules ==
 
== Projective indecomposable modules ==
  
Labelling the simple <math>B</math>-modules by <math>S_1, S_2, S_3, S_4, S_5, S_6, S_7</math>, the projective indecomposable modules have Loewy structure as follows:
 
  
<math>\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}
 
</math>
 
  
 
== Irreducible characters ==
 
== Irreducible characters ==

Latest revision as of 14:39, 14 September 2026

M(16,14,6) - [math]k(C_2 \times ((C_2)^3 : C_7))[/math]
[[File: |250px]]
Representative: [math]k((C_2)^4 : C_7)[/math]
Defect groups: [math](C_2)^4[/math]
Inertial quotients: [math]C_7[/math]
[math]k(B)=[/math] 16
[math]l(B)=[/math] 7
[math]{\rm mf}_k(B)=[/math] 1
[math]{\rm Pic}_k(B)=[/math]  
Cartan matrix: [math]\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)[/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]\mathcal{O} (C_2 \times ((C_2)^3 : C_7))[/math]
Decomposition matrices: See below
[math]{\rm mf}_\mathcal{O}(B)=[/math] 1
[math]{\rm Pic}_{\mathcal{O}}(B)=[/math]
[math]PI(B)=[/math]
Source algebras known? No
Source algebra reps:
[math]k[/math]-derived equiv. classes known? Yes
[math]k[/math]-derived equivalent to: M(16,14,7)
[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:

Basic algebra

Other notatable representatives

Covering blocks and covered blocks

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

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

Projective indecomposable modules

Irreducible characters

All irreducible characters have height zero.

Decomposition matrix

[math]\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)[/math]

Back to [math](C_2)^4[/math]