The new system is essentially dense in the upper-triangular part and appears to require O([n.
The back substitution, in both methods, involves an upper-triangular matrix with a definite rank structure.
Branching rules in the ring of superclass functions of unipotent upper-triangular
q]), the group of n by n upper-triangular matrices over the field [F.
The goal of this paper is to study the connection between upper-triangular nilpotent matrices over [F.
This is done by SCPRE that can generate a block diagonal preconditioner or a block upper-triangular
n](q) acts on both sides of the algebra of strictly upper-triangular
In this paper, we instead use an encoding of interval orders by upper-triangular
matrices without zero rows and zero columns (we call such matrices Fishburn matrices.
matrix T was constructed as follows.
Let the m-th hook sum of an upper-triangular
matrix A = [[a.
We will show that each of these rotators preserves the upper-triangular
structure of B, effecting a swap of two eigenvalues.
It has become clear in recent years that the representation theory finite group of unipotent upper-triangular
matrix groups Un(q) can lead to a similarly rich combinatorial theory.