9 , 2

The Hecke algebra for the Symmetric Group on 11 Letters, with the Partition [ 9, 2 ] in characteristic 2 .

The Module M

The module M is the permutation module over the prime field of chacteristic 2, having point stablilizer equal to the Young subgroup of the partition. The dimension of M is 55 .

The dimensions of the irreducible submodules modules are 44, 10, 1 .

The module M has radical filtration (Loewy series)
1, 2, 3


The module M has socle filtration (socle series)
1, 2, 3


The Action Algebra

The action algebra A is the image of kG in the k-endomorphism ring of M. It's simple modules are the irreducible submodules of M.

The dimensions of the projective modules are 44, 10, 1 .

The cartan matrix of A is



The determinant of the Cartan matrix is 1.

The blocks of A consist of the following irreducible modules: