Displaying 281 – 300 of 941

Showing per page

Factorizable matrices

Miroslav Fiedler, Frank J. Hall (2013)

Special Matrices

We study square matrices which are products of simpler factors with the property that any ordering of the factors yields a matrix cospectral with the given matrix. The results generalize those obtained previously by the authors.

Factorization of CP-rank- 3 completely positive matrices

Jan Brandts, Michal Křížek (2016)

Czechoslovak Mathematical Journal

A symmetric positive semi-definite matrix A is called completely positive if there exists a matrix B with nonnegative entries such that A = B B . If B is such a matrix with a minimal number p of columns, then p is called the cp-rank of A . In this paper we develop a finite and exact algorithm to factorize any matrix A of cp-rank 3 . Failure of this algorithm implies that A does not have cp-rank 3 . Our motivation stems from the question if there exist three nonnegative polynomials of degree at most four that...

Factorization of matrices associated with classes of arithmetical functions

Shaofang Hong (2003)

Colloquium Mathematicae

Let f be an arithmetical function. A set S = x₁,..., xₙ of n distinct positive integers is called multiple closed if y ∈ S whenever x|y|lcm(S) for any x ∈ S, where lcm(S) is the least common multiple of all elements in S. We show that for any multiple closed set S and for any divisor chain S (i.e. x₁|...|xₙ), if f is a completely multiplicative function such that (f*μ)(d) is a nonzero integer whenever d|lcm(S), then the matrix ( f ( x i , x i ) ) having f evaluated at the greatest common divisor ( x i , x i ) of x i and x i as its...

Factorizations for q-Pascal matrices of two variables

Thomas Ernst (2015)

Special Matrices

In this second article on q-Pascal matrices, we show how the previous factorizations by the summation matrices and the so-called q-unit matrices extend in a natural way to produce q-analogues of Pascal matrices of two variables by Z. Zhang and M. Liu as follows [...] We also find two different matrix products for [...]

Fermat's Equation in Matrices

Khazanov, Alex (1995)

Serdica Mathematical Journal

The Fermat equation is solved in integral two by two matrices of determinant one as well as in finite order integral three by three matrices.

Focal power.

Hartwig, Robert E., Maroulas, John (2005)

ELA. The Electronic Journal of Linear Algebra [electronic only]

Fredholm determinants

Henry McKean (2011)

Open Mathematics

The article provides with a down to earth exposition of the Fredholm theory with applications to Brownian motion and KdV equation.

Gap universality of generalized Wigner and β -ensembles

László Erdős, Horng-Tzer Yau (2015)

Journal of the European Mathematical Society

We consider generalized Wigner ensembles and general β -ensembles with analytic potentials for any β 1 . The recent universality results in particular assert that the local averages of consecutive eigenvalue gaps in the bulk of the spectrum are universal in the sense that they coincide with those of the corresponding Gaussian β -ensembles. In this article, we show that local averaging is not necessary for this result, i.e. we prove that the single gap distributions in the bulk are universal. In fact,...

Currently displaying 281 – 300 of 941