Álvarez Solano, VíctorArmario Sampalo, José AndrésFrau García, María DoloresGudiel Rodríguez, FélixGüemes Alzaga, María BelénMartín García, ElenaOsuna Lucena, Amparo2019-06-132019-06-132010Álvarez Solano, V., Armario Sampalo, J.A., Frau García, M.D., Gudiel Rodríguez, F., Güemes Alzaga, M.B., Martín García, E. y Osuna Lucena, A. (2010). ACS Searching for D4t-Hadamard Matrices. En ANTS 2010 : 7th International Conference on Swarm Intelligence (368-375), Brussels, Belgium: Springer.978-3-642-15460-70302-9743https://hdl.handle.net/11441/87397An Ant Colony System (ACS) looking for cocyclic Hadamard matrices over dihedral groups D4t is described. The underlying weighted graph consists of the rooted trees described in [1], whose vertices are certain subsets of coboundaries. A branch of these trees defines a D4t- Hadamard matrix if and only if two conditions hold: (i) Ii = i − 1 and, (ii) ci = t, for every 2 ≤ i ≤ t, where Ii and ci denote the number of ipaths and i-intersections (see [3] for details) related to the coboundaries defining the branch. The pheromone and heuristic values of our ACS are defined in such a way that condition (i) is always satisfied, and condition (ii) is closely to be satisfied.application/pdfengAttribution-NonCommercial-NoDerivatives 4.0 Internacionalhttp://creativecommons.org/licenses/by-nc-nd/4.0/Cocyclic Hadamard matrixAnt colony systemi-pathi-intersectioninfo:eu-repo/semantics/conferenceObjectinfo:eu-repo/semantics/openAccesshttps://doi.org/10.1007/978-3-642-15461-4_33