Now showing items 2-21 of 209

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      A combinatorial overview of the Hopf algebra of MacMahon symmetric functions  [Article]

      Rosas Celis, Mercedes Helena; Rota, Gian-Carlo; Stein, Joel (Springer, 2002-11)
      A MacMahon symmetric function is a formal power series in a finite number of alphabets that is invariant under the diagonal action of the symmetric group. In this article, we give a combinatorial overview of the Hopf algebra ...
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      A complete diophantine characterization of the rational torsion of an elliptic curve  [Article]

      García Selfa, Irene; Tornero Sánchez, José María (Springer, 2012-01)
      We give a complete characterization for the rational torsion of an elliptic curve in terms of the (non–)existence of integral solutions of a system of diophantine equations.
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      A computational approach to the D-module of meromorphic functions  [Article]

      Castro Jiménez, Francisco Jesús; Ucha Enríquez, José María (2001)
      Let D be a divisor in Cn. We present methods to compare the D-module of the meromorphic functions O[∗D] to some natural approximations. We show how the analytic case can be treated with computations in the Weyl algebra.
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      A duality approach to the symmetry of Bernstein-Sato polynomials of free divisors  [Article]

      Narváez Macarro, Luis (Elsevier, 2015-08-20)
      In this paper we prove that the Bernstein-Sato polynomial of any free divisor for which the D[s]-module D[s]h s admits a Spencer logarithmic resolution satisfies the symmetry property b(−s−2) = ±b(s). This applies in ...
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      A fast solution to the conjugacy problem in the four-strand braid group  [Article]

      Calvez, Matthieu; Wiest, Bert (De Gruyter, 2014-09)
      We present an algorithm for solving the conjugacy search problem in the fourstrand braid group. The computational complexity is cubic with respect to the braid length.
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      A flatness property for filtered D-modules  [Article]

      Castro Jiménez, Francisco Jesús; Granger, Michel (European Mathematical Society, 2007)
      Let M be a coherent module over the ring DX of linear differential operators on an analytic manifold X and let Z1, · · · , Zk be k germs of transverse hypersurfaces at a point x ∈ X. The Malgrange-Kashiwara V-filtrations ...
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      A geometric characterization of the upper bound for the span of the Jones polynomial  [Article]

      González-Meneses López, Juan; González Manchón, Pedro María (World Scientific, 2011-07)
      Let D be a link diagram with n crossings, sA and sB its extreme states and |sAD| (resp. |sBD|) the number of simple closed curves that appear when smoothing D according to sA (resp. sB). We give a general formula for the ...
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      A geometric description of the extreme Khovanov cohomology  [Article]

      González-Meneses López, Juan; González Manchón, Pedro María; Silvero Casanova, Marithania (Cambridge University Press, 2018-06)
      We prove that the hypothetical extreme Khovanov cohomology of a link is the cohomology of the independence simplicial complex of its Lando graph. We also provide a family of knots having as many non-trivial extreme Khovanov ...
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      A note on K-theory and triangulated derivators  [Article]

      Muro Jiménez, Fernando; Raptis, George (Elsevier, 2011-08-01)
      In this paper we show an example of two differential graded algebras that have the same derivator K-theory but non-isomorphic Waldhausen K-theory. We also prove that Maltsiniotis’s comparison and localization conjectures ...
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      A rigid local system with monodromy group 2.J2  [Article]

      Katz, Nicholas M.; Rojas León, Antonio (Elsevier, 2019-05)
      We exhibit a rigid local system of rank six on the affine line in characteristic p = 5 whose arithmetic and geometric monodromy groups are the finite group 2.J2 (J2 the Hall-Janko sporadic group) in one of its two ...
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      Abelian varieties over number fields, tame ramification and big Galois image  [Article]

      Arias de Reyna Domínguez, Sara; Kappen, Christian (International Press, 2013)
      Given a natural number n ≥ 1 and a number field K, we show the existence of an integer ℓ0 such that for any prime number ℓ ≥ ℓ0, there exists a finite extension F/K, unramified in all places above ℓ, together with a ...
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      Acylindrical hyperbolicity and Artin-Tits groups of spherical type  [Article]

      Calvez, Matthieu; Wiest, Bert (Springer, 2017)
      We prove that, for any irreducible Artin-Tits group of spherical type G, the quotient of G by its center is acylindrically hyperbolic. This is achieved by studying the additional length graph associated to the classical ...
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      Alexander-Conway polynomial state model and link homology  [Article]

      Kauffman, Louis H.; Silvero Casanova, Marithania (World Scientific Publishing, 2016-03)
      This paper shows how the Formal Knot Theory state model for the Alexander-Conway polynomial is related to Knot Floer Homology. In particular we prove a parity result about the states in this model that clarifies certain ...
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      Algebraic computation of some intersection D-modules  [Article]

      Calderón Moreno, Francisco Javier; Narváez Macarro, Luis (Springer, 2006)
      Let X be a complex analytic manifold, D ⊂ X a locally quasi-homogeneous free divisor, E an integrable logarithmic connection with respect to D and L the local system of the horizontal sections of E on X − D. In this ...
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      Algorithmic Invariants for Alexander Modules  [Chapter of Book]

      Gago Vargas, Manuel Jesús; Hartillo Hermoso, Isabel; Ucha Enríquez, José María (2006)
      Let $G$ be a group given by generators and relations. It is possible to compute a presentation matrix of a module over a ring through Fox's differential calculus. We show how to use Gröbner bases as an algorithmic tool ...
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      An algebraic approach to Integer Portfolio problems  [Article]

      Castro Jiménez, Francisco Jesús; Gago Vargas, Manuel Jesús; Hartillo Hermoso, Isabel; Puerto Albandoz, Justo; Ucha Enríquez, José María (2011-05-01)
      Integer variables allow the treatment of some portfolio optimization problems in a more realistic way and introduce the possibility of adding some natural features to the model. We propose an algebraic approach to ...
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      An improved test set approach to nonlinear integer problems with applications to engineering design  [Article]

      Gago Vargas, Manuel Jesús; Hartillo Hermoso, Isabel; Puerto Albandoz, Justo; Ucha Enríquez, José María (Springer, 2015-11)
      Many problems in engineering design involve the use of nonlinearities and some integer variables. Methods based on test sets have been proposed to solve some particular problems with integer variables, but they have not ...
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      El Año Mundial de las Matemáticas en Andalucía  [Article]

      Pérez Jiménez, Antonio de Jesús (Federación Española de Profesores de Matemáticas, 2001-06)
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      Arithmetic motivic Poincaré series of toric varieties  [Article]

      Cobo Pablos, Helena; González Pérez, Pedro Daniel (Mathematical Sciences Publishers, 2013)
      The arithmetic motivic Poincaré series of a variety V defined over a field of characteristic zero is an invariant of singularities that was introduced by Denef and Loeser by analogy with the Serre–Oesterlé series in ...
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      Álgebra computacional y programación entera no lineal  [Article]

      Gago Vargas, Manuel Jesús; Hartillo Hermoso, Isabel (Real Sociedad Matemática Española, 2016)