共查询到20条相似文献,搜索用时 15 毫秒
1.
Beatriz Pascual-Escudero 《Journal of Pure and Applied Algebra》2019,223(6):2598-2614
Let X be an algebraic variety defined over a field of characteristic zero, and let be a point in the closed subset of maximum multiplicity of X. We provide a criterion, given in terms of arcs, to determine whether ξ is isolated in . More precisely, we use invariants of arcs derived from the Nash multiplicity sequence to characterize when ξ is an isolated point in . 相似文献
2.
3.
4.
5.
6.
Let R be a polynomial ring over a field and I an ideal generated by three forms of degree three. Motivated by Stillman's question, Engheta proved that the projective dimension of is at most 36, although the example with largest projective dimension he constructed has . Based on computational evidence, it had been conjectured that . In the present paper we prove this conjectured sharp bound. 相似文献
7.
8.
We construct a minimal free resolution of the semigroup ring in terms of minimal resolutions of and when is a numerical semigroup obtained by gluing two numerical semigroups and . Using our explicit construction, we compute the Betti numbers, graded Betti numbers, regularity and Hilbert series of , and prove that the minimal free resolution of has a differential graded algebra structure provided the resolutions of and possess them. We discuss the consequences of our results in small embedding dimensions. Finally, we give an extension of our main result to semigroups in . 相似文献
9.
Imanol Mozo Carollo 《Journal of Pure and Applied Algebra》2021,225(2):106490
This paper approaches the construction of the universal completion of the Riesz space of continuous real functions on a completely regular frame L in two different ways. Firstly as the space of continuous real functions on the Booleanization of L. Secondly as the space of nearly finite Hausdorff continuous functions on L. The former has no counterpart in the classical theory, as the Booleanization of a spatial frame is not spatial in general, and it offers a lucid way of representing the universal completion as a space of continuous real functions. As a corollary we obtain that and have isomorphic universal completions if and only if the Booleanization of L and M are isomorphic and we characterize frames L such that is universally complete as almost Boolean frames. The application of this last result to the classical case of the space of continuous real functions on a topological space X characterizes those spaces X for which is universally complete. Finally, we present a pointfree version of the Maeda-Ogasawara-Vulikh representation theorem and use it to represent the universal completion of an Archimedean Riesz space with weak unit as a space of continuous real functions on a Boolean frame. 相似文献
10.
11.
12.
Rubén A. Hidalgo Maximiliano Leyton-Álvarez 《Journal of Pure and Applied Algebra》2019,223(7):3057-3070
Let be a generalized Fermat pair of the type . If is the set of fixed points of the non-trivial elements of the group H, then F is exactly the set of hyperosculating points of the standard embedding . We provide an optimal lower bound (this being sharp in a dense open set of the moduli space of the generalized Fermat curves) for the Weierstrass weight of these points. 相似文献
13.
《Discrete Mathematics》2022,345(2):112690
For a bipartite graph G with parts X and Y, an X-interval coloring is a proper edge coloring of G by integers such that the colors on the edges incident to any vertex in X form an interval. Denote by the minimum k such that G has an X-interval coloring with k colors. Casselgren and Toft (2016) [12] asked whether there is a polynomial such that if G has maximum degree at most Δ, then . In this short note, we answer this question in the affirmative; in fact, we prove that a cubic polynomial suffices. We also deduce some improved upper bounds on for bipartite graphs with small maximum degree. 相似文献
14.
Mi Hee Park 《Journal of Pure and Applied Algebra》2019,223(9):3980-3988
There are many Noetherian-like rings. Among them, we are interested in SFT-rings, piecewise Noetherian rings, and rings with Noetherian prime spectrum. Some of them are stable under polynomial extensions but none of them are stable under power series extensions. We give partial answers to some open questions related with stabilities of such rings. In particular, we show that any mixed extensions over a zero-dimensional SFT ring R are also SFT-rings, and that if R is an SFT-domain such that is integrally closed for each prime ideal P of R, then is an SFT-ring. We also give a direct proof that if R is an SFT Prüfer domain, then is an SFT-ring. Finally, we show that the power series extension over a Prüfer domain R is piecewise Noetherian if and only if R is Noetherian. 相似文献
15.
《Discrete Mathematics》2022,345(12):113083
Let G be a graph, the order of G, the connectivity of G and k a positive integer such that . Then G is said to be k-extendable if it has a matching of size k and every matching of size k extends to a perfect matching of G. A Hamiltonian path of a graph G is a spanning path of G. A bipartite graph G with vertex sets and is defined to be Hamiltonian-laceable if such that and for every pair of vertices and , there exists a Hamiltonian path in G with endpoints p and q, or and for every pair of vertices , there exists a Hamiltonian path in G with endpoints p and q. Let G be a bipartite graph with bipartition . Define to be a maximum integer such that and (1) for each non-empty subset S of X, if , then , and if , then ; and (2) for each non-empty subset S of Y, if , then , and if , then ; and (3) if there is no non-negative integer satisfying (1) and (2).Let G be a bipartite graph with bipartition such that and . In this paper, we show that if , then G is Hamiltonian-laceable; or if , then for every pair of vertices and , there is an -path P in G with . We show some of its corollaries in k-extendable, bipartite graphs and a conjecture in k-extendable graphs. 相似文献
16.
17.
Let R be an affine domain of dimension over a field of characteristic 0 and . Let be a local complete intersection ideal of height n such that . This paper examines under what condition I is surjective image of a projective D-module of rank n. 相似文献
19.
In this paper we construct a ring A which has annihilator condition (a.c.) and we show that neither nor has this property. This answers in negative a question asked by Hong, Kim, Lee and Nielsen. We also show that there is an algebra A which does not have annihilator condition while both and have this property. 相似文献
20.
In this paper, we generalize the notion of functional graph. Specifically, given an equation with variables X and Y over a finite field of odd characteristic, we define a digraph by choosing the elements in as vertices and drawing an edge from x to y if and only if . We call this graph as equational graph. In this paper, we study the equational graph when choosing with a polynomial over and λ a non-square element in . We show that if f is a permutation polynomial over , then every connected component of the graph has a Hamiltonian cycle. Moreover, these Hamiltonian cycles can be used to construct balancing binary sequences. By making computations for permutation polynomials f of low degree, it appears that almost all these graphs are strongly connected, and there are many Hamiltonian cycles in such a graph if it is connected. 相似文献