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991.
992.
A. E. Brouwer 《Combinatorica》1982,2(4):333-340
We prove that any regular near hexagon with 729 vertices and lines of size 3 is derived from the ternary Golay code, thus
settling the last case in doubt among the regular near hexagons with lines of size 3. 相似文献
993.
Summary It is well known that some information is needed for accelerating efficiently the convergence of a sequence. We show in this article that, for several families of sequences, there is no algorithm accelerating the convergence of every sequence of the family. 相似文献
994.
Dieter Lutz 《Aequationes Mathematicae》1981,23(1):197-203
In this note it is shown that the Cauchy problem associated with the infinitesimal generatorA of a strongly continuous operator cosine function remains uniformly well-posed under bounded time-dependent perturbations ofA. 相似文献
995.
Convergence in probability for Toeplitz weighted sums is obtained for convex tight random elements in D[0, 1] under pointwise conditions. The almost sure convergence of the weighted sums is proved for independent, convex tight random elements and for independent, identically distributed random elements. Special techniques and concepts are developed in order to obtain these results in the Skorohod topology of D[0, 1]. 相似文献
996.
In this self-contained exposition, results are developed concerning one-factorizations of complete graphs, and incidence matrices are used to turn these factorization results into embedding theorems on Steiner triple systems. The result is a constructive graphical proof that a Steiner triple system exists for any order congruent to 1 or 3 modulo 6. A pairing construction is then introduced to show that one can also obtain triple systems which are cyclically generated. 相似文献
997.
998.
A. Jiménez-lópez P. Maireles-Torres P. Olivera-Pastor E. Rodriguez-Castellón M. J. Hudson P. Sylvester 《Journal of inclusion phenomena and macrocyclic chemistry》1990,9(3):207-217
The intercalation of amines into -tin(IV) hydrogen phosphate, -Sn(HP04)2·H20, (-SnP) can occur to give mono- or bilayers of the guest molecule. The distribution and orientation of the amines is influenced by geometrical factors, acidity of the guest molecule and moreover, the degree of charge localisation of the guest organic cations. Regarding the monolayer formation, there are two possibilities. The first is that aromatic amines form monolayers with parallel orientation of the amine with respect to the phosphate layer, when the charge is delocalised over the aromatic ring. Monolayer formation with perpendicular orientation occurs when the positive charge is localised in opposite parts of the aromatic ring molecule. Bilayer formation occurs when the positive charge is localised in one part of the molecule and simultaneous interaction with two adjacent layers is not possible. 相似文献
999.
Donald E Knuth 《Journal of Combinatorial Theory, Series A》1974,16(3):398-400
A simple proof is given that limn?t8(log2 log2gn)/n = 1, where gn denotes the number of distinct combinatorial geometries on n point 相似文献
1000.