Through the matrix rank method, this paper gives necessary and sufficient conditions for a partitioned matrix to have generalized inverses with Banachiewicz-Schur forms. In addition, this paper investigates the idempotency of generalized Schur complements in a partitioned idempotent matrix.

This note deals with a matricial Schur function arising from a completely indeterminate Nehari problem. The Schur algorithm is characterized by a unilateral shift for a Nehari sequence. c ⃝ 2017 Elsevier Inc. All rights reserved. MSC: 42C05; 42A56; 42A70

Recently, it was proved that every p-Schur ring over an abelian group of order p is Schurian. In this paper, we prove that every commutative p-Schur ring over a non-abelian group of order p is Schurian.

Generalizing recent work of Brundan and Kleshchev, we introduce grading on Dipper-James’ q-Schur algebra, and prove a graded analogue of the Leclerc and Thibon’s conjecture on the decomposition numbers of the q-Schur algebra.

Consider the problem of partitioning n nonnegative numbers into p parts, where part i can be assigned ni numbers with ni lying in a given range. The goal is to maximize a Schur convex function F whose i th argument is the sum of numbers assigned to part i . The shape of a partition is the vector consisting of the sizes of its parts, further, a shape (without referring to a particular partition)...

The Schur group of a commutative ring, R, with identity consists of all classes in the Brauer group of R which contain a homomorphlc image of a group ring RG for some finite group G. It is the purpose of ths article to continue an investigation of this group which was introduced in earler work as a natural gene=allzatlon of the Schur group of a field. We generalize certain facts pertaining to t...

We completely characterize the appearance of Schur functions corresponding to partitions of the form ν = (1a, b) (hook shapes) in the Schur function expansion of the plethysm of two Schur functions, sλ[sμ] = ∑ ν aλ,μ,νsν . Specifically, we show that no Schur functions corresponding to hook shapes occur unless λ and μ are both hook shapes and give a new proof of a result of Carbonara, Remmel and...

We define a 0-Hecke action on composition tableaux, and then use it to derive 0-Hecke modules whose quasisymmetric characteristic is a quasisymmetric Schur function. We then relate the modules to the weak Bruhat order and use them to derive a new basis for quasisymmetric functions. We also classify those modules that are tableau-cyclic and likewise indecomposable. Finally, we develop a restrict...

As a natural generalisation of q-Schur algebras associated with the Hecke algebra Hr,R (of the symmetric group), we introduce the Q-q-Schur superalgebra associated with the Hecke-Clifford superalgebra H r,R, which, by definition, is the endomorphism algebra of the induced H r,R-module from certain q-permutation modules over Hr,R. We will describe certain integral bases for these superalgebras i...