Endomorphism Rings of Permutation Modules over Maximal Young Subgroups
نویسندگان
چکیده
Let K be a field of characteristic two, and let λ be a two-part partition of some natural number r. Denote the permutation module corresponding to the (maximal) Young subgroup Σλ in Σr byM . We construct a full set of orthogonal primitive idempotents of the centraliser subalgebra SK(λ) = 1λSK(2, r)1λ = EndKΣr (M ) of the Schur algebra SK(2, r). These idempotents are naturally in one-to-one correspondence with the 2-Kostka numbers.
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