Now showing items 93-112 of 211

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      Improvements of the Weil bound for Artin-Schreier curves  [Article]

      Rojas León, Antonio; Wan, Daqing (Springer, 2011-10)
      For the Artin-Schreier curve y q − y = f(x) defined over a finite field Fq of q elements, the celebrated Weil bound for the number of Fq r -rational points can be sharp, especially in super-singular cases and when r is ...
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      Improving an algorithm to solve multiple simultaneous conjugacy problems in braid groups  [Article]

      González-Meneses López, Juan (American Mathematical Society, 2005)
      There are recent cryptographic protocols that are based on Multiple Simultaneous Conjugacy Problems in braid groups. We improve an algorithm, due to Sang Jin Lee and Eonkyung Lee, to solve these problems, by applying a ...
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      Inequalities between Littlewood–Richardson coefficients  [Article]

      Bergeron, François; Biagioli, Riccardo; Rosas Celis, Mercedes Helena (Elsevier, 2006-05)
      We prove that a conjecture of Fomin, Fulton, Li, and Poon, associated to ordered pairs of partitions, holds for many infinite families of such pairs. We also show that the bounded height case can be reduced to checking ...
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      Integral points in rational polygons: a numerical semigroup approach  [Article]

      Márquez Campos, Guadalupe; Ramírez Alfonsín, Jorge Luis; Tornero Sánchez, José María (Springer, 2016)
      In this paper we use an elementary approach by using numerical semigroups (specifically, those with two generators) to give a formula for the number of integral points inside a right-angled triangle with rational ...
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      Invariants and coinvariants of the symmetric group in noncommuting variables  [Article]

      Bergeron, Nantel; Reutenauer, Christophe; Rosas Celis, Mercedes Helena; Zabrocki, Mike (University of Toronto Press, 2008)
      We introduce a natural Hopf algebra structure on the space of noncommutative symmetric functions. The bases for this algebra are indexed by set partitions. We show that there exists a natural inclusion of the Hopf algebra ...
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      Irregular hypergeometric D-modules  [Article]

      Fernández Fernández, María Cruz (E, 2010-08-01)
      We study the irregularity of hypergeometric D-modules MA(β) via the explicit construction of Gevrey series solutions along coordinate subspaces in X = C n. As a consequence, we prove that along coordinate hyperplanes the ...
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      Irregular modified A-Hypergeometric systems  [Article]

      Castro Jiménez, Francisco Jesús; Fernández Fernández, María Cruz; Koike, Tatsuya; Takayama, Nobuki (American Mathematical Society, 2015)
      A modified A-hypergeometric system is a system of differential equations for the function f(t w · x) where f(y) is a solution of an A-hypergeometric system in n variables and w is an n dimensional integer vector, which is ...
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      K-theory of derivators revisited  [Article]

      Muro Jiménez, Fernando; Raptis, George (Mathematical Sciences Publishers, 2017)
      We define a K-theory for pointed right derivators and show that it agrees with Waldhausen K-theory in the case where the derivator arises from a good Waldhausen category. This K-theory is not invariant under general ...
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      Katz-Radon transform of l-adic representations  [Article]

      Rojas León, Antonio (Duke University Press, 2012)
      We prove a simple explicit formula for the local Katz-Radon transform of an l-adic representation of the Galois group of the fraction field of a strictly henselian discrete valuation ring with positive residual characteristic, ...
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      L-functions of symmetric powers of the generalized Airy family of exponential sums  [Article]

      Haessig, C. Douglas; Rojas León, Antonio (2011-12)
      This paper looks at the L-function of the kth symmetric power of the -sheaf Aif over the affine line associated to the generalized Airy family of exponential sums. Using ℓ-adic techniques, we compute the degree of this ...
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      La labor docente del profesor de matemáticas  [Article]

      Aranda Plata, Antonio (Sociedad Española de Matemática Aplicada, 2003)
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      Large Galois images for Jacobian varieties of genus 3 curves  [Article]

      Arias de Reyna Domínguez, Sara; Armana, Cécile; Karemaker, Valentijn; Rebolledo, Marusia; Thomas, Lara; Vila Oliva, Núria (Polish Academy of Sciences, Institute of Mathematics, 2016)
      Given a prime number ℓ ≥ 5, we construct an infinite family of three-dimensional abelian varieties over Q such that, for any A/Q in the family, the Galois representation ρA,ℓ : GQ → GSp6 (Fℓ) attached to the ℓ-torsion of ...
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      Le théorème de continuité de la division dans les anneaux d'opérateurs différentiels  [Article]

      Mebkhout, Zoghman; Narváez Macarro, Luis (De Gruyter, 1998)
      In this paper we prove the continuity of Weierstrass-Hironaka division of finite order linear differential operators over a complex analytic manifold X with respect to the induced topology by a canonical one of Fréchet ...
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      Le théorème du symbole total d’un opérateur différentiel p-adique  [Article]

      Mebkhout, Zoghman; Narváez Macarro, Luis (Consejo Superior de Investigaciones Científicas, 2010)
      Let X † be a smooth †-scheme (in the sense of Meredith) over a complete discrete valuation ring (V,m) of unequal characteristics (0, p) and let D†X†/V be the sheaf of V -linear endomorphisms of OX† whose reduction modulo ...
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      Linear nested Artin approximation theorem for algebraic power series  [Article]

      Castro Jiménez, Francisco Jesús; Popescu, Dorin; Rond, Guillaume (Springer, 2018)
      We give an elementary proof of the nested Artin approximation Theorem for linear equations with algebraic power series coefficients. Moreover, for any Noetherian local subring of the ring of formal power series, we clarify ...
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      Local convolution of l-adic sheaves on the torus  [Article]

      Rojas León, Antonio (Springer, 2013-08)
      For K and L two l-adic perverse sheaves on the one-dimensional torus Gm,k¯ over the algebraic closure of a finite field, we show that the local monodromies of their convolution K ∗ L at its points of non-smoothness ...
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      Localization at hyperplane arrangements: combinatorics and D-modules  [Article]

      Álvarez Montaner, Josep; Castro Jiménez, Francisco Jesús; Ucha Enríquez, José María (Elsevier, 2007-10-15)
      We describe an algorithm deciding if the annihilating ideal of the meromorphic function 1 f , where f = 0 defines an arrangement of hyperplanes, is generated by linear differential operators of order 1. The algorithm is ...
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      Locally quasi-homogeneous free divisors are Koszul free  [Article]

      Calderón Moreno, Francisco Javier; Narváez Macarro, Luis (MAIK Nauka/Interperiodica, 2002)
      Let X be a complex analytic manifold and D ⊂ X be a free divisor. If D is locally quasi-homogeneous, then the logarithmic de Rham complex associated to D is quasi-isomorphic to Rj∗(CX\D), which is a perverse sheaf. On the ...
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      Logarithmic cohomology of the complement of a plane curve  [Article]

      Calderón Moreno, Francisco Javier; Mond, David; Narváez Macarro, Luis; Castro Jiménez, Francisco Jesús (Springer, 2002-03)
      Let D, x be a plane curve germ. We prove that the complex Ω•(log D)x computes the cohomology of the complement of D, x only if D is quasihomogeneous. This is a partial converse to a theorem of F.J. Castro-Jiménez, D. Mond ...
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      Logarithmic differential operators and logarithmic de Rham complexes relative to a free divisor  [Article]

      Calderón Moreno, Francisco Javier (Elsevier, 1999)
      We prove a structure theorem for differential operators in the 0-th term of the V-filtration relative to a free divisor. manifold. As an application, we give a formula for the logarithmic de Rham complex with respect to a ...