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101.
Catherine O’Neil 《Journal of Number Theory》2005,112(2):369-385
Let p denote a prime, and K a field of characteristic prime to p and containing the pth roots of unity. For p equal to 3 and 5, the author finds a scheme Tp and a family of genus one curves over Tp such that any genus one curve defined over the field K of index p whose Jacobian elliptic curve E has is isomorphic to a curve lying over a K-point of Tp. The author then relates the explicit presentation of such families to the program of descent on elliptic curves. 相似文献
102.
In this paper, we study some packings in a cube, namely, how to pack n points in a cube so as to maximize the minimal distance. The distance is induced by the L1-norm which is analogous to the Hamming distance in coding theory. Two constructions with reasonable parameters are obtained,
by using some results from a function field including divisor class group, narrow ray class group, and so on. We also present
some asymptotic results of the two packings. 相似文献
103.
Paulo H. Viana Jaime E. A. Rodriguez 《Bulletin of the Brazilian Mathematical Society》2005,36(1):39-58
A curve defined over a finite field is maximal or minimal according to whether the number of rational points attains the upper or the lower bound in Hasse-Weils theorem, respectively. In the study of maximal curves a fundamental role is played by an invariant linear system introduced by Rück and Stichtenoth in [6]. In this paper we define an analogous invariant system for minimal curves, and we compute its orders and its Weierstrass points. In the last section we treat the case of curves having genus three in characteristic two. 相似文献
104.
N. Z. Mamadalieva L. N. Zibareva R. Lafont L. Dainan Z. Saatov 《Chemistry of Natural Compounds》2004,40(6):574-578
Research results on the isolation and identification of ecdysteroids from plants of the Silene L. genus were presented.Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 472–475, November–December, 2004.This revised version was published online in April 2005 with a corrected cover date. 相似文献
105.
Peter?BeelenEmail author Arnaldo?Garcia Henning?Stichtenoth 《Bulletin of the Brazilian Mathematical Society》2004,35(2):151-164
In this article we derive strong conditions on the defining equations of asymptotically good Artin-Schreier towers. We will show that at most three kinds of defining equations can give rise to a recursively defined good tower, if we restrict ourselves to prime degrees.
1A. Garcia and H. Stichtenoth did part of thiswork during their stay at Sabanci University, Istanbul, Turkey (Sept. 2002).
2A. Garcia was partially supported by PRONEX # 662408/1996-3 (CNPq-Brazil). 相似文献
106.
该文证明了如下结果:设犌为直径为4的简单图,若犌不含3阶完全子图犓3,则犌的Betti亏数ξ(犌)≤4,因此有犌的最大亏格γ犕(犌)≥
12β(犌)-2. 相似文献
107.
A relative embedding of a connected graph is an embedding of the graph in some surface with respect to some closed walks,
each of which bounds a face of the embedding. The relative maximum genus of a connected graph is the maximum of integerk with the property that the graph has a relative embedding in the orientable surface withk handles. A polynomial algorithm is provided for constructing relative maximum genus embedding of a graph if the relative
tree of the graph is planar. Under this condition, just like maximum genus embedding, a graph does not have any locally strict
maximum genus. 相似文献
108.
109.
Let V ∪SW be a Heegaard splitting of M,such that αM = α-W = F1 ∪ F2 and g(S) = 2g(F1)= 2g(F2). Let V * ∪S*W * be the self-amalgamation of V ∪SW. We show if d(S) 3 then S* is not a topologically minimal surface. 相似文献
110.
In this paper, we investigate the existence of infinitely many solutions for the following fractional Hamiltonian systems: ( FHS ) where α ∈ (1 ∕ 2,1), , , and are symmetric and positive definite matrices for all , , and ? W is the gradient of W at u. The novelty of this paper is that, assuming L is coercive at infinity, and W is of subquadratic growth as | u | → + ∞ , we show that (FHS) possesses infinitely many solutions via the genus properties in the critical theory. Recent results in the literature are generalized and significantly improved. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献