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941.
A. A. Ryabinin 《Mathematical Notes》1998,64(5):629-633
The system
, where Λ={λ
n
} is the set of zeros (of multiplicitiesm
n
) of the Fourier transform
of a singular Cantor-Lebesgue measure, is examined. We prove thate(Λ) is complete and minimal inL
p
(−a, a) withp≥1, and that |L(x+iy)|2 does not satisfy the Muckenhoupt condition on any horizontal line Imz=y≠0 in the complex plane. This implies thate(Λ) does not have the property of convergence extension.
Translated fromMatematicheskie Zametki, Vol. 64, No. 5, pp. 728–733, November, 1998. 相似文献
942.
A. Makagon A. G. Miamee B. S. W. Schrö der 《Proceedings of the American Mathematical Society》1998,126(6):1821-1825
In this note a recursive type condition for positivity of the angle between past and future for -variate stationary sequences is provided. In the case it gives a simple different proof of a result due to Solev and Tserkhtsvadze on basicity of bivariate stationary sequences.
943.
Ulrich Haag 《K-Theory》1998,13(1):81-108
We study the relation of Z2equivariant and Z2graded KK-theory. The former is the universal stable, split exact and homotopy invariant theory on the category of Z2graded C*algebras and graded homomorphisms (Theorem 1). We obtain an abstract characterization for the product of the graded KK-functor (Theorem 2). We give generalizations to Z2graded C*algebras of the Universal Coefficent Theorem, Künneth Theorem and Künneth Theorem for tensor products. We prove some results about graded crossed products of Thom isomorphism and Pimsner-Voiculescu type (Theorem 3 and Corollary 2) and compute an example. We obtain a split surjective map KK(A,B) KK(A0,B0) commuting with products, where A0is a canonically defined trivially graded algebra for any Z2-graded A. 相似文献
944.
Claude L. Schochet 《K-Theory》1998,14(2):197-199
In this note we correct a mistake in K-Theory 10 (1996), 49–72. In that paper we asserted that under bootstrap hypotheses the short exact sequence
which arises in the computation ofKK(A,B)
(is a split sequence. This is not always the case. ThusKK(A,B)
(decomposes into the three components
and
However, this is a decomposition in the sense of composition series, not as three direct summands. The same correction applies to the Milnor sequence. If there is no primepfor which bothK(A)
(andK(B)
*haveptorsion then the decomposition is indeed as direct summands. The other results of the paper are unaffected. 相似文献
945.
We show that the Asplund property of Banach spaces is not only sufficient but also a necessary condition for the fulfillment of some basic results in nonsmooth analysis involving Fréchet-like normals and subdifferentials as well as their sequential limits. In this way we obtain new characterizations of Asplund spaces within the framework of nonsmooth analysis. Then we study several versions of smooth variational principles in Asplund spaces, provide necessary and sufficient conditions for the validity of such principles, and establish their relationships with certain subdifferential properties of lower semicontinuous functions. 相似文献
946.
Hayato Nawa 《Journal of statistical physics》1998,91(1-2):439-458
We consider the blow-up problem for the nonlinear Schrödinger equation with quartic self-interacting potential on
. We exhibit a class of initial data leading to the blow-up solutions which have at least two L
2-concentration points. 相似文献
947.
János Folláth 《Periodica Mathematica Hungarica》2008,57(1):73-81
In a series of papers Mauduit and Sárközy (partly with coauthors) studied finite pseudorandom binary sequences and they constructed sequences with strong pseudorandom properties. In these constructions fields with prime order were used. In this paper a new construction is presented, which is based on finite fields of order 2 k . 相似文献
948.
Jakob Jonsson 《Journal of Combinatorial Theory, Series A》2008,115(8):1504-1526
Building on work by Bouc and by Shareshian and Wachs, we provide a toolbox of long exact sequences for the reduced simplicial homology of the matching complex Mn, which is the simplicial complex of matchings in the complete graph Kn. Combining these sequences in different ways, we prove several results about the 3-torsion part of the homology of Mn. First, we demonstrate that there is nonvanishing 3-torsion in whenever , where . By results due to Bouc and to Shareshian and Wachs, is a nontrivial elementary 3-group for almost all n and the bottom nonvanishing homology group of Mn for all n≠2. Second, we prove that is a nontrivial 3-group whenever . Third, for each k?0, we show that there is a polynomial fk(r) of degree 3k such that the dimension of , viewed as a vector space over Z3, is at most fk(r) for all r?k+2. 相似文献
949.
Stefano Serra-Capizzano Per Sundqvist 《Journal of Computational and Applied Mathematics》2008,219(2):518
Given an approximating class of sequences {{Bn,m}n}m for {An}n, we prove that (X+ being the pseudo-inverse of Moore–Penrose) is an approximating class of sequences for , where {An}n is a sparsely vanishing sequence of matrices An of size dn with dk>dq for k>q,k,qN. As a consequence, we extend distributional spectral results on the algebra generated by Toeplitz sequences, by including the (pseudo) inversion operation, in the case where the sequences that are (pseudo) inverted are distributed as sparsely vanishing symbols. Applications to preconditioning and a potential use in image/signal restoration problems are presented. 相似文献
950.