Now showing items 21-34 of 34

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      Generating partial Hadamard matrices as solutions to a Constraint Satisfaction Problem characterizing cliques  [Presentation]

      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  [Presentation]

      Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Falcón Ganfornina, Raúl Manuel; Frau García, María Dolores; Gudiel Rodríguez, Félix (2017-07)
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      Gröbner bases and cocyclic Hadamard matrices  [Article]

      Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Falcón Ganfornina, Raúl Manuel; Frau García, María Dolores; Gudiel Rodríguez, Félix (Elsevier, 2018)
      Hadamard ideals were introduced in 2006 as a set of nonlin-ear polynomial equations whose zeros are uniquely related ...
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      Homological models for semidirect products of finitely generated Abelian groups  [Article]

      Álvarez Solano, Víctor; Frau García, María Dolores; Real Jurado, Pedro; Armario Sampalo, José Andrés (2012)
      Let G be a semidirect product of finitely generated Abelian groups. We provide a method for constructing an explicit ...
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      Matrices cocíclicas de Hadamard sobre productos semidirectos  [Presentation]

      Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; Real Jurado, Pedro (Alberto Márquez, 2002)
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      On Cocyclic Hadamard Matrices over Goethals-Seidel Loops  [Article]

      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 (MDPI, 2020)
      About twenty-five years ago, Horadam and de Launey introduced the cocyclic development of designs, from which the notion ...
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      On higher dimensional cocyclic Hadamard matrices  [Article]

      Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; Real Jurado, Pedro (2015)
      Provided that a cohomological model for G is known, we describe a method for constructing a basis for n-cocycles over G, ...
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      On ZZt × ZZ2 2-cocyclic Hadamard matrices  [Article]

      Álvarez Solano, Víctor; Gudiel Rodríguez, Félix; Güemes Alzaga, María Belén (Wiley, 2015)
      A characterization of ZZt × ZZ22 -cocyclic Hadamard matrices is described, de- pending on the notions of distributions, ...
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      (Pseudo)-cocyclic (structured) Hadamard matrices over (quasi)groups  [Presentation]

      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  [Presentation]

      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  [Presentation]

      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 ...
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      The homological reduction method for computing cocyclic Hadamard matrices  [Article]

      Álvarez Solano, Víctor; Armario Sampalo, José Andrés; Frau García, María Dolores; Real Jurado, Pedro (2009)
      An alternate method for constructing (Hadamard) cocyclic matrices over a finite group GG is described. Provided that a ...
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      Transferring TTP-structures via contraction  [Article]

      Frau García, María Dolores; Real Jurado, Pedro; Armario Sampalo, José Andrés; Álvarez Solano, Víctor (2005)