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20162021
most citedOn diagonal entries of Cartan matrices of p-blocks

2 citations · 5 across the 6 of their papers we have counts for

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math.RT2021

Central ideals and Jacobson radicals of blocks of group algebras

Yoshihiro Otokita

We study the relationship between the central ideals and the Jacobson radicals of blocks of group algebras.In particular, we characterize the blocks with the property that the squa…

math.RT2019

Loewy lengths of centers of blocks and exponents of defect groups

Yoshihiro Otokita

In this paper we study the Loewy structure of the center of a block of a finite group with respect to an algebraically closed field of prime characteristic. We first state a n…

math.RT2018★ 1 cited

Notes on Loewy series of centers of -blocks

Yoshihiro Otokita

The present paper describes some results on the Loewy series of the center of a modular group algebra in order to solve a problem on the number of irreducible ordinary characters.…

math.RT2017★ 1 cited

Loewy lengths of centers of blocks II

Burkhard Külshammer, Yoshihiro Otokita, Benjamin Sambale

Let ZB be the center of a p-block B of a finite group with defect group D. We show that the Loewy length LL(ZB) of ZB is bounded by provided D is not cyclic. If…

math.RT2016

On centers of blocks with non-cyclic defect groups

Yoshihiro Otokita

In this short note we study the center ZB of a block B of a finite group over an algebraically closed field of prime characteristic through its Loewy length llZB. A result of Okuya…

math.RT2016★ 1 cited

Some studies on Loewy lengths of centers of p-blocks

Yoshihiro Otokita

In this paper, we investigate some relations between the Loewy lengths of the centers of blocks of group algebras and its defect groups. In particular, we give a new upper bound of…

math.RT2016★ 2 cited

On diagonal entries of Cartan matrices of p-blocks

Yoshihiro Otokita

In this short note, we show some inequalities on Cartan matrices, centers and socles of blocks of group algebras. Our main theorems are generalizations of the facts on dimension of…