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排序方式: 共有618条查询结果,搜索用时 156 毫秒
21.
Ch. F. D. McCoy 《Algebra and Logic》2002,41(5):295-305
The notion of
3
0
-categoricity in linear orderings and Boolean algebras is examined. We provide a proof for the fact that there are uncountably many relatively
3
0
-categorical linear orderings, and furnish a proof of another fact which suggests that the (unrelatively)
3
0
-categorical linear orderings may be very difficult to classify. In stark contrast to these results for linear orderings, a complete classification of the relatively
3
0
-categorical Boolean algebras is given. 相似文献
22.
23.
Mariusz Rabus Saharon Shelah 《Proceedings of the American Mathematical Society》1999,127(9):2573-2581
For every uncountable cardinal there is a ccc Boolean algebra whose topological density is .
24.
Bent函数的一般构造法 总被引:7,自引:0,他引:7
本文用概率方法给出小项表示的布尔函数谱的性质,据此得到了Bent函数的特征矩阵的等价刻画,原则上给出了Bent函数的一般构造法,并为Bent函数的计数问题提供了一个模型。文中还提出了Bent矩阵的概念,考察了Bent矩阵的性质,并借助Bent矩阵得到由已知Bent函数构造新的Bent函数构造新的Bent函数的方法。 相似文献
25.
Various conditions ensuring that an atomic effect algebra is a Boolean algebra are presented.
PACS: 02.10.-v. 相似文献
26.
27.
Computable Homogeneous Boolean Algebras and a Metatheorem 总被引:1,自引:0,他引:1
P. E. Alaev 《Algebra and Logic》2004,43(2):73-87
We consider computable homogeneous Boolean algebras. Previously, countable homogeneous Boolean algebras have been described up to isomorphism and a simple criterion has been found for the existence of a strongly constructive (decidable) isomorphic copy for such. We propose a natural criterion for the existence of a constructive (computable) isomorphic copy. For this, a new hierarchy of
-computable functions and sets is introduced, which is more delicate than Feiner's. Also, a metatheorem is proved connecting computable Boolean algebras and their hyperarithmetical quotient algebras. 相似文献
28.
Scott Kravitz 《Journal of Algebraic Combinatorics》2004,20(1):61-70
Let (B
n) be the order complex of the Boolean algebra and let B(n, k) be the part of (B
n) where all chains have a gap at most k between each set. We give an action of the symmetric group S
l on the l-chains that gives B(n, k) a Hodge structure and decomposes the homology under the action of the Eulerian idempontents. The S
n action on the chains induces an action on the Hodge pieces and we derive a generating function for the cycle indicator of the Hodge pieces. The Euler characteristic is given as a corollary.We then exploit the connection between chains and tabloids to give various special cases of the homology. Also an upper bound is obtained using spectral sequence methods.Finally we present some data on the homology of B(n, k). 相似文献
29.
M.?V.?MenshikovEmail author S.?Yu.?Popov M.?Vachkovskaia 《Bulletin of the Brazilian Mathematical Society》2003,34(3):417-435
We study the multiscale (fractal) percolation in dimension
greater than or equal to 2, where the model at each level is the
Poisson Boolean model [[, ]]. Also, the random radius
is supposed to be
unbounded. We prove that if the rate of Poisson field is less
than some critical value, then by choosing the scaling parameter
large enough one can assure that there is no multiscale
percolation. Another result of this paper is that if the
expectation of 2d is finite, then the
expectation of the size of the cluster raised to the power is
also finite for small , which is a generalization of one of the
results of [8].1 Partially supported by FAPESP (97/12826–6,
02/02984–3) and CNPq (300676/00–0)2 Partially supported by FAPESP (00/11462–5,
02/03012–5) 相似文献
30.
A. Aizpuru F.J. Pérez-Fernández 《Journal of Mathematical Analysis and Applications》2003,284(1):89-96
Several classical results on uniform convergence of unconditionally Cauchy series are generalized to weakly unconditionally Cauchy series. This uniform convergence is characterized through subalgebras and subfamilies of . A generalization of the Orlicz-Pettis theorem is also proved by mean of subalgebras of . 相似文献