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排序方式: 共有5993条查询结果,搜索用时 359 毫秒
991.
Márk Horváth 《Discrete Mathematics》2008,308(19):4378-4388
An (n,a,b)-perfect double cube is a b×b×b sized n-ary periodic array containing all possible a×a×a sized n-ary array exactly once as subarray. A growing cube is an array whose cj×cj×cj sized prefix is an (nj,a,cj)-perfect double cube for , where and n1<n2<?. We construct the smallest possible perfect double cube (a 256×256×256 sized 8-ary array) and growing cubes for any a. 相似文献
992.
Soonsik Kwon 《Journal of Differential Equations》2008,245(9):2627-2659
In this paper we prove that the following fifth-order equation arising from the KdV hierarchy
993.
In this paper we mainly study the Cauchy problem for the generalized shallow water wave equation in the Sobolev space Hs of lower order s. Using the crucial bilinear estimates in the Fourier transform restriction spaces related to the shallow water wave equation, we establish local well-posedness in Hs with any . 相似文献
994.
Zhi-Hong Sun 《Journal of Number Theory》2008,128(2):280-312
Let [x] be the integral part of x. Let p>5 be a prime. In the paper we mainly determine , , and in terms of Euler and Bernoulli numbers. For example, we have
995.
We give a constructive deciphering for a generalization of the Quillen-Suslin theorem due to Maroscia and Brewer & Costa stating that finitely generated projective modules over , where is a Prüfer domain with Krull dimension ≤1, are extended from . 相似文献
996.
Imre Patyi 《Mathematische Annalen》2008,341(2):455-482
Let X be a Banach space with a countable unconditional basis (e.g., X = ℓ
2 Hilbert space), Ω ⊂ X pseudoconvex open, E → Ω a locally trivial holomorphic vector bundle with a Banach space Z for fiber type, the sheaf of germs of holomorphic sections of E → Ω, and Z
1 the Banach space . Then and Ω × Z
1 are holomorphically isomorphic, is acyclic and E is so to speak stably trivial over Ω in a generalized sense. We also show that if E is continuously trivial over Ω, then E is holomorphically trivial over Ω. In particular, if Z = ℓ
2 or Ω is contractible, then E is holomorphically trivial over Ω. Some applications are also given.
To my dear little daughter, Sári Mangala, on her third birthday.
Supported in part by a Research Initiation Grant from Georgia State University. 相似文献
997.
Sönke Rollenske 《Mathematische Annalen》2008,341(3):623-628
The Frölicher spectral sequence of a compact complex manifold X measures the difference between Dolbeault cohomology and de Rham cohomology. If X is Kähler then the spectral sequence collapses at the E 1term and no example with d n ≠ 0 for n > 3 has been described in the literature.We construct for n ≥ 2 nilmanifolds with left-invariant complex structure X n such that the n-th differential d n does not vanish. This answers a question mentioned in the book of Griffiths and Harris. 相似文献
998.
Hiroaki Shimomura 《Mathematische Zeitschrift》2008,259(2):355-361
This paper concerns positive-definite functions on infinite-dimensional groups G. Our main results are as follows: first, we claim that if G has a σ-finite measure μ on the Borel field whose right admissible shifts form a dense subgroup G
0, a unique (up to equivalence) unitary representation (H, T) with a cyclic vector corresponds to through a method similar to that used for the G–N–S construction. Second, we show that the result remains true, even if we
go to the inductive limits of such groups, and we derive two kinds of theorems, those taking either G or G
0 as a central object. Finally, we proceed to an important example of infinite-dimensional groups, the group of diffeomorphisms
on smooth manifolds M, and see that the correspondence between positive-definite functions and unitary representations holds for under a fairy mild condition. For a technical reason, we impose condition (c) in Sect. 2 on the measure space throughout this paper. It is also a weak condition, and it is satified, if G is separable, or if μ is Radon.
This research was partially supported by a Grant-in-Aid for Scientific Research (No.18540184), Japan Socieity of the Promotion
of Science. 相似文献
999.
In (Kaniuth and Kumar in Math. Proc. Camb. Phil. Soc. 131, 487–494, 2001) Hardy’s uncertainty principle for was generalized to connected and simply connected nilpotent Lie groups. In this paper, we extend it further to connected
nilpotent Lie groups with non-compact centre. Concerning the converse, we show that Hardy’s theorem fails for a connected
nilpotent Lie group G which admits a square integrable irreducible representation and that this condition is necessary if the simply connected
covering group of G satisfies the flat orbit condition. 相似文献
1000.
Rachelle C. DeCoste 《manuscripta mathematica》2008,127(3):309-343
We study the distribution of closed geodesics on nilmanifolds Γ \ N arising from a 2-step nilpotent Lie algebra constructed from an irreducible representation of a compact semisimple Lie algebra on a real finite dimensional vector space U. We determine sufficient conditions on the semisimple Lie algebra for Γ \ N to have the density of closed geodesics property where Γ is a lattice arising from a Chevalley rational structure on . 相似文献