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      ACS Searching for D4t-Hadamard Matrices 

      Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; Gudiel Rodríguez, Félix; Güemes Alzaga, María Belén; Martín García, Elena; Osuna Lucena, Amparo (Springer, 2010)
      An Ant Colony System (ACS) looking for cocyclic Hadamard matrices over dihedral groups D4t is described. The underlying ...
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      An algorithm for computing the first homology groups of CDGAs with linear differential 

      Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; Real Jurado, Pedro; Silva Gallardo, Beatriz (Research Institute for Symbolic Computation, 1999)
      We design here a primary platform for computing the basic homological information of Commutative Differential Graded ...
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      Computing “Small” 1–Homological Models for Commutative Differential Graded Algebras 

      Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; González Díaz, Rocío; Jiménez Rodríguez, María José; Real Jurado, Pedro; Silva Gallardo, Beatriz (Springer, 2000)
      We use homological perturbation machinery specific for the algebra category [13] to give an algorithm for computing the ...
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      Error correcting codes from quasi-Hadamard matrices 

      Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; Martín García, Elena; Osuna Lucena, Amparo (Springer, 2007)
      Levenshtein described in [5] a method for constructing error correcting codes which meet the Plotkin bounds, provided ...
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      Generating partial Hadamard matrices as solutions to a Constraint Satisfaction Problem characterizing cliques 

      Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Falcón Ganfornina, Raúl Manuel; Frau García, María Dolores; Gudiel Rodríguez, Félix; Güemes Alzaga, María Belén; Osuna Lucena, Amparo (2017-07)
      A procedure is described looking for partial Hadamard matrices, as cliques of a particular subgraph Gt of Ito’s Hadamard ...
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      Gröbner bases and cocyclic Hadamard matrices 

      Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Falcón Ganfornina, Raúl Manuel; Frau García, María Dolores; Gudiel Rodríguez, Félix (2017-07)
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      Homological perturbation theory and computability of Hochschild and cyclic homologies of CDGAs 

      Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Real Jurado, Pedro; Silva Gallardo, Beatriz (Diffiety Institute of the Russian Academy of Natural Sciences, 1997)
      We establish an algorithm computing the homology of commutative differential graded algebras (briefly, CDGAs). The main ...
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      On (−1, 1)-Matrices of Skew Type with the Maximal Determinant and Tournaments 

      Armario Sampalo, José Andrés (Springer, 2014)
      Skew Hadamard matrices of order n give the solution to the question of finding the largest possible n by n determinant ...
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      On the computability of the p-local homology of twisted cartesian products of Eilenberg-Mac Lane spaces 

      Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Real Jurado, Pedro (Universidade do Minho, 1997)
      Working in the framework of the Simplicial Topology, a method for calculating the p-local homology of a twisted cartesian ...
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      El Proyecto CHATA 

      Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; González Díaz, Rocío; Jiménez Rodríguez, María José; Real Jurado, Pedro; Silva Gallardo, Beatriz (Universidad de Sevilla, 2001)
      En este art´ıculo, se pretende dar una visi´on general y lo m´as divulgativa posible sobre los prop´ositos y objetivos ...
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      (Pseudo)-cocyclic (structured) Hadamard matrices over (quasi)groups 

      Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Falcón Ganfornina, Raúl Manuel; Frau García, María Dolores; Gudiel Rodríguez, Félix; Güemes Alzaga, María Belén; Kotsireas, Ilias (2017)
      Progressing on a survey of the state of the art of cocyclic constructions for Hadamard matrices, we will prove that the ...
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      Rooted Trees Searching for Cocyclic Hadamard Matrices over D4t 

      Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; Gudiel Rodríguez, Félix; Osuna Lucena, Amparo (Springer, 2009)
      A new reduction on the size of the search space for cocyclic Hadamard matrices over dihedral groups D4t is described, in ...
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      Searching for partial Hadamard matrices 

      Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; Gudiel Rodríguez, Félix; Güemes Alzaga, María Belén; Martín García, Elena; Osuna Lucena, Amparo (Universidade de Santiago de Compostela, Servicio de Publicaciones, 2010)
      Three algorithms looking for pretty large partial Hadamard ma- trices are described. Here “large” means that hopefully ...