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51.
Blaise Heider 《代数通讯》2013,41(5):2156-2162
To describe the representation theory of the quantum Weyl algebra at an lth primitive root γ of unity, Boyette, Leyk, Plunkett, Sipe, and Talley found all nonsingular irreducible matrix solutions to the equation yx ? γxy = 1, assuming yx ≠ xy. In this note, we complete their result by finding and classifying, up to equivalence, all irreducible matrix solutions (X, Y), where X is singular. 相似文献
52.
Stefan G. Samko 《Applicable analysis》2013,92(3):269-299
We consider the periodization of the Riesz fractional integrals (Riesz potentials) of two variables and show that already in this case we come across different effects, depending on whether we use the repeated periodization, first in one variable, and afterwards in another one, or the so called double periodization. We show that the naturally introduced doubly-periodic Weyl-Riesz kernel of order 0< f <2 in general coincides with the periodization of the Riesz kernel, the repeated periodization being possible for all 0< f <2 , while the double one is applicable only for 0< f <1 . This is obtained as a realization of a certain general scheme of periodization, both repeated and double versions. We prove statements on coincidence of the corresponding periodic and nonperiodic convolutions and give an application to the case of the Riesz kernel. 相似文献
53.
Mathematical Notes - 相似文献
54.
Hai-Lun Lin 《Theoretical chemistry accounts》1991,79(1):43-52
Summary This is the first paper of a series of two, which enables the evaluation ofU(n) generator matrix elements in the non-canonical Weyl tableau basis adapted to subgroupU(n
1)×U(n
2). In this paper the explicit closed formulae for subduction coefficients are presented. These formulae will become useful through an inductive method to be presented in the second paper. 相似文献
55.
56.
57.
Marilena?Munteanu 《Bulletin of the Brazilian Mathematical Society》2007,38(1):39-50
In this paper we propose a technique of approximation for the generalized Riemann-Stieltjes integral and we found an analogue
for Newton-Cotes formulas in the case n = 2 and n = 3.
*Beneficiary of a Socrates fellowship at the Department of Mathematics, University of Study of Cagliari, Via Ospedale, n.
72, Cagliari, 09124, Italy, in the period February – July 2002. 相似文献
58.
Jonas Sjöstrand 《Journal of Combinatorial Theory, Series A》2007,114(7):1182-1198
We characterise the permutations π such that the elements in the closed lower Bruhat interval [id,π] of the symmetric group correspond to non-taking rook configurations on a skew Ferrers board. It turns out that these are exactly the permutations π such that [id,π] corresponds to a flag manifold defined by inclusions, studied by Gasharov and Reiner.Our characterisation connects the Poincaré polynomials (rank-generating function) of Bruhat intervals with q-rook polynomials, and we are able to compute the Poincaré polynomial of some particularly interesting intervals in the finite Weyl groups An and Bn. The expressions involve q-Stirling numbers of the second kind, and for the group An putting q=1 yields the poly-Bernoulli numbers defined by Kaneko. 相似文献
59.
We have investigated two conformally flat tilted Bianchi Type-V cosmological models in general relativity. To get a determinate
solution, we have assumed a supplementary conditionA =B
n between metric potentials wheren is a constant. The behaviour of the model forn = 2 is discussed in detail. Various physical and geometrical aspects of the models are also discussed. 相似文献
60.
TOSHIKI NAKASHIMA 《Compositio Mathematica》1997,108(1):1-33
Crystal base of the level 0 part of the modified quantum affine algebra Uq(sl2)_0 is given by path. Weyl group actions, extremal vectors and crystal structure of all irreducible components are described explicitly. 相似文献