4 papers
Multivariate orthogonal polynomials: quantum decomposition, deficiency rank and support of measure
Ameur Dhahri, Nobuaki Obata, Hyun Jae Yoo
In this paper we investigate the multivariate orthogonal polynomials based on the theory of interacting Fock spaces. Our framework is on the same stream line of the recent paper by…
On Quadratic Embedding Constants of Star Product Graphs
Wojciech Młotkowski, Nobuaki Obata
A connected graph is of QE class if it admits a quadratic embedding in a Hilbert space, or equivalently if the distance matrix is conditionally negative definite, or equivalent…
Asymptotic Spectral Distributions of Distance -Graphs of Cartesian Product Graphs
Yuji Hibino, Hun Hee Lee, Nobuaki Obata
Let be a finite connected graph on two or more vertices and the distance -graph of the -fold Cartesian power of . For a fixed , we obtain explicitly…
Distance k-graphs of hypercube and q-Hermite polynomials
Hun Hee Lee, Nobuaki Obata
We will prove that some weighted graphs on the distance -graph of hypercubes approximate the -Hermite polynomial of a -gaussian variable by providing an appropriate matrix…