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51.
设含幺交换环R对其乘法子集T的分式环为RT,交换幺半群S在其子半群∑处局部化为S∑本文证明了R[S]对于A的分环式环R[S]AM 构于半群环RT[S∑]。 相似文献
52.
53.
Anna Varvak 《Journal of Combinatorial Theory, Series A》2005,112(2):1-307
For an element w in the Weyl algebra generated by D and U with relation DU=UD+1, the normally ordered form is w=∑ci,jUiDj. We demonstrate that the normal order coefficients ci,j of a word w are rook numbers on a Ferrers board. We use this interpretation to give a new proof of the rook factorization theorem, which we use to provide an explicit formula for the coefficients ci,j. We calculate the Weyl binomial coefficients: normal order coefficients of the element (D+U)n in the Weyl algebra. We extend these results to the q-analogue of the Weyl algebra. We discuss further generalizations using i-rook numbers. 相似文献
54.
Carstenelsner 《Mathematische Nachrichten》1998,189(1):243-256
Let ξ be a real irrational number, and a ≧ 0, b ≧ 0, s > 1 be integers. A theorem of S. UCHIYAMA states that there are infinitely many pairs of integers u and v ≠ 0 such that OVBARξ?u/vOVBAR ≤ s2/4v2 and u ? a, v ? b mod s, provided that it is not a ? 6 ? 0 mod s. It is shown that this result is best-possible for all integers s > 1. 相似文献
55.
王家正 《应用数学与计算数学学报》2006,20(2):77-82
Stieltjes型分叉连分式在有理插值问题中有着重要的地位,它通过定义反差商和混合反差商构造给定结点上的二元有理函数,我们将Stieltjes型分叉连分式与二元多项式结合起来,构造Stieltje- Newton型有理插值函数,通过定义差商和混合反差商,建立递推算法,构造的Stieltjes-Newton型有理插值函数满足有理插值问题中所给的插值条件,并给出了插值的特征定理及其证明,最后给出的数值例子,验证了所给算法的有效性. 相似文献
56.
T. Komatsu 《Lithuanian Mathematical Journal》2006,46(4):417-431
The tanh-type, tan-type, and e-type Hurwitz continued fractions have been generalized by the author. In this paper, we study a generalized form
of e2-type Hurwitz continued fractions by using confluent hypergeometric functions. We also obtain a similar type of Tasoev continued
fractions.
Published in Lietuvos Matematikos Rinkinys, Vol. 46, No. 4, pp. 513–531, October–December, 2006. 相似文献
57.
58.
P. Sajkiewicz P. J. Phillips 《Journal of polymer science. Part A, Polymer chemistry》1995,33(6):949-955
FTIR measurements of sol fractions were carried out in order to assess side reactions during dicumyl peroxide (DCP) crosslinking of linear low density polyethylenes (LLDPEs) with homogeneous distribution of short chain branching. The changes of methyl and olefinic unsaturation concentration were measured as a function of degree of branching and DCP content. The changes of methyl and vinylidene concentration indicate that the scission probability has greater significance for the samples with initial branch content above 31 CH3/1000 C and increases with increasing DCP concentration. The analysis of trans-vinylene concentration indicates that the probability of disproportionation also increases with increasing DCP content. The changes of methyl concentration in the sol fraction of the sample containing initially ca. 23 CH3/1000 C with increasing DCP content could be interpreted using the dependence of crosslinking efficiency on branch content found previously for some range of branch concentration. © 1995 John Wiley & Sons, Inc. 相似文献
59.
A review and some new results are presented for several cluster statistics models, solutions of which can be reduced to difference equations. Mathematical techniques suitable for solving these equations are surveyed. 相似文献
60.
R. G. Stoneham 《BIT Numerical Mathematics》1970,10(4):481-500
In the computing literature, there are few detailed analytical studies of the global statistical characteristics of a class of multiplicative pseudo-random number generators.We comment briefly on normal numbers and study analytically the approximately uniform discrete distribution or (j,)-normality in the sense of Besicovitch for complete periods of fractional parts {x
0
1
i
/p} on [0, 1] fori=0, 1,..., (p–1)p–1–1, i.e. in current terminology, generators given byx
n+1
1
x
n mod p wheren=0, 1,..., (p–1)p
–1–1,p is any odd prime, (x
0,p)=1,
1 is a primitive root modp
2, and 1 is any positive integer.We derive the expectationsE(X, ),E(X
2, ),E(X
nXn+k); the varianceV(X, ), and the serial correlation coefficient k. By means of Dedekind sums and some results of H. Rademacher, we investigate the asymptotic properties of k for various lagsk and integers 1 and give numerical illustrations. For the frequently used case =1, we find comparable results to estimates of Coveyou and Jansson as well as a mathematical demonstration of a so-called rule of thumb related to the choice of
1 for small k.Due to the number of parameters in this class of generators, it may be possible to obtain increased control over the statistical behavior of these pseudo-random sequences both analytically as well as computationally. 相似文献