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61.
A.?A.?YambartsevEmail author A.?A.?Zamyatin 《Bulletin of the Brazilian Mathematical Society》2003,34(3):361-388
We consider a Markov chain that describes the evolution of
two interacting strings of symbols. The transitions
probalitities of this Markov chain depend only on the rightmost
symbols of both strings. The main goal of the present paper is
to prove a limit theorem (stabilization law): the distribution
of the rightmost symbols converges to some limit correlation
function.1 Partially supported by FAPESP (2002/01501-9) and
RFBR (02-01-00415)2 Partially supported by RFBR
(02-01-00415) 相似文献
62.
63.
Matvei Libine 《Journal of Functional Analysis》2003,203(1):197-236
This article provides a geometric bridge between two entirely different character formulas for reductive Lie groups and answers the question posed by Schmid (in: Deformation Theory and Symplectic Geometry, Mathematical Physics Studies, Vol. 20, Kluwer Academic Publishers, Dordrecht, 1997, pp. 259-270).A corresponding problem in the compact group setting was solved by Berline et al. (Heat Kernels and Dirac Operators, Springer, Berlin, 1992) by an application of the theory of equivariant forms and particularly the fixed point integral localization formula. This article (besides its representation-theoretical significance) provides a whole family of examples where it is possible to localize integrals to fixed points with respect to an action of a noncompact group. Moreover, a localization argument given here is not specific to the particular setting considered in this article and can be extended to a more general situation.There is a broadly accessible article (Libine, A Localization Argument for Characters of Reductive Lie Groups: An Introduction and Examples, 2002, math.RT/0208024) which explains how the argument works in the case, where the key ideas are not obstructed by technical details and where it becomes clear how it extends to the general case. 相似文献
64.
Franciszek Hugon Szafraniec 《Numerical Algorithms》2003,33(1-4):475-483
We discuss a possibility of deciding whether measures representing a moment sequence or realizing orthogonality of polynomials have atoms. This is done on the real line and in several variables. 相似文献
65.
All finite fields
q (q 2, 3, 4, 5, 7, 9, 13, 25, 121) contain a primitive element for which + 1/ is also primitive. All fields of square order
q
2 (q 3, 5) contain an element of order q + 1 for which + 1/ is a primitive element of the subfield
q. These are unconditional versions of general asymptotic results. 相似文献
66.
M. K. Bos. 《Mathematics of Computation》2003,72(244):2001-2012
In this paper, an algorithm for computing the principal character for affine Lie algebras is discussed and presented. The principal characters discovered using this program are given and/or proven. Results include level 2 and 3 character formulas in and the sole existence of the Rogers-Ramanujan products in , , , , , , . 相似文献
67.
We obtain upper bounds for mixed exponential sums of the type
where pm is a prime power with m⩾ 2 and X is a multiplicative character (mod pm). If X is primitive or p⫮(a, b) then we obtain |S(χ,f,p
m)| ⩽2np
2/3 m. If X is of conductor p and p⫮( a, b) then we get the stronger bound |S(χ,f,p
m)|⩽np
m/2.
This paper is dedicated to Prof. Wang Yuan on the occasion of his 70th birthday. 相似文献
68.
Generalized Steiner systems GS(2, 4, v, g) were first introduced by Etzion and were used to construct optimal constant weight codes over an alphabet of size g + 1 with minimum Hamming distance 5, in which each codeword has length v and weight 4. Etzion conjectured that the necessary conditions v 1 (mod 3) and v ; 7 are also sufficient for the existence of a GS(2,4,v,2). Except for the example of a GS(2,4,10,2) and some recursive constructions given by Etzion, nothing else is known about this conjecture. In this paper, Weil's theorem on character sum estimates is used to show that the conjecture is true for any prime power v 7 (mod 12) except v = 7, for which there does not exist a GS(2,4,7,2). 相似文献
69.
In [2] E. Dobrowolski and K.S. Williams considered a problem of obtaining estimates for the sum
n=a+1
a+N
f(n),for a certain class of functions f. One specific application of their result is a new method for estimating character sums. In particular, they obtain a form of the Pólya-Vinogradov inequality with the constant 1/(2 log 2). In this note we improve their estimates and obtain, in particular, a form of the Pólya-Vinogradov inequality with the constant 1/(3 log 3). A nice feature of our estimate is that it is obtained by a very simple argument. 相似文献
70.
Mark L. Lewis 《Algebras and Representation Theory》2001,4(5):469-489
Let G be a solvable group with five character degrees. We show that the derived length of G is at most 5. This verifies that the Taketa inequality, dl(G)|cd(G)|, is valid for solvable groups with at most five character degrees. 相似文献