# Hadamard ideals and Hadamard matrices with two circulant cores

@article{Kotsireas2006HadamardIA, title={Hadamard ideals and Hadamard matrices with two circulant cores}, author={Ilias S. Kotsireas and Christos Koukouvinos and Jennifer Seberry}, journal={Eur. J. Comb.}, year={2006}, volume={27}, pages={658-668} }

We apply computational algebra methods to the construction of Hadamard matrices with two circulant cores, given by Fletcher, Gysin and Seberry. We introduce the concept of Hadamard ideal, to systematize the application of computational algebra methods for this construction. We use the Hadamard ideal formalism to perform exhaustive search constructions of Hadamard matrices with two circulant cores for the twelve orders 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 52. The total number of such… Expand

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