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Proyecciones (Antofagasta)

versión impresa ISSN 0716-0917

Proyecciones (Antofagasta) vol.32 no.4 Antofagasta dic. 2013 


On generalized binomial series and strongly regular graphs


Vasco Moço Mano, Luís António de Almeida Vieira
University of Porto, Portugal

Enide Andrade Martins
University of Aveiro, Portugal


We consider a strongly regular graph, G, and associate a three dimensional Euclidean Jordan algebra, V, to its adjacency matrix A. Then, by considering binomial series of Hadamard powers of the idem-potents of the unique complete system of orthogonal idempotents of V associated to A, we establish feasibility conditions for the existence of strongly regular graphs.

Keyword : Strongly regular graph Euclidean Jordan algebra Matrix analysis.


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Vasco Moco Mano
Department of Mathematics
Faculty of Sciences
University of Porto
Rua do Campo Alegre
687; 4169-007, Porto, Portugal
e-mail :


Enide Andrade Martins
CIDMA - Center for Research and Development in Math. and Appl.
Department of Mathematics
University of Aveiro
3810-193 Aveiro
e-mail :


Luis Antonio de Almeida Vieira
CMUP - Center of Research of Mathematics
Department of Mathematics
Faculty of Sciences
University of Porto
Rua do Campo Alegre
687; 4169-007 Porto
e-mail :

1. Enide Andrade Martins is supported in part by FEDER funds through COMPETE Operational Programme Factors of Competitiveness ("Programa Operacional Factores de Competitividade") and by Portuguese funds through the Center for Research and Develpment in Mathematics and Applications and the Portuguese Foundation for Science and Technology (iFCT - Fundaçao paraa Ciência e a Tecnologia") within project PEest-C/MAT/UI4106/ 2011 with COMPETE number FCOMP-01-0124-FEDER-022690 and Project PTDC/MAT/ 112276/2009.

2. Luis Vieira research funded by the European Regional Development Fund through the program COMPETE and by the Portuguese Government through the FCT -Fundaçao paraa Ciência e a Tecnologia under the project PEest-C/MAT/UI0144/2011.

Received : April 2013. Accepted : August 2013.

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