External Scientific Member
My main field of research is combinatorial matrix theory and spectral graph theory, and their abundant multi-disciplinary applications. I am also interested in trigonometric sums and the connections between abstract and linear algebras.

Carlos Martins da Fonseca (Figueira da Foz, Portugal, 1968) is a full professor at the Kuwait College of Science and Technology. He is Doctor of Science by the Technical University – Sofia, Bulgaria. He is the editor-in-chief of Special Matrices, a journal on structured matrices by De Gruyter.
  • -DSc. in Mathematics (2016), Technical University - Sofia, Bulgaria
  • -PhD in Mathematics (1996 - 2000), University of Coimbra, Portugal
  • -BSc. in Mathematics (1986 - 1991), University of Coimbra, Portugal

Some previous Publications:

  • -A short note on the determinant of a Sylvester-Kac type matrix, International Journal of Nonlinear Sciences and Numerical Simulation 21 (2020), no. 3-4, 361-362

  • -Tridiagonal matrices and spectral properties of some graph classes (with M. Andelic, Z. Du, and S.K. Simic, Czechoslovak Mathematical Journal, 70 (2020), no. 4, 1125-1138

  • -On the determinant of general pentadiagonal matrices (with L. Losonczi), Publicationes Mathematicae Debrecen, 97 (2020), 507-523

  • -On some pentadiagonal matrices: Their determinants and inverse, (with L. Losonczi), Annales Universitatis Scientiarum Budapest. Sectio Computatorica 51 (2020), 39-50.

  • -The interesting spectral interlacing property for a certain tridiagonal matrix} (with E. Kilic and A. Pereira), Electronic Journal of Linear Algebra 36 (2020), 587-598

  • -On a closed form for derangement numbers: An elementary proof, RACSAM Revista de la Real Academia de Ciencias Exactas, Físicas y Naturales. Serie A. Matemáticas, 114 (2020), 146

  • -Ninety years of k-tridiagonal matrices (with V. Kowalenko and L. Losonczi), Studia Scientiarum Mathematicarum Hungarica 57 (2020), 298–311

  • -On nonsingular acyclic M-matrices whose inverse is also acyclic (with Z. Du and L. Losonczi), RACSAM Revista de la Real Academia de Ciencias Exactas, Físicas y Naturales. Serie A. Matemáticas 114 (2020), 138

  • -On the Bruhat rank of a Boolean F-matrix} (with Z. Du), Bulletin Mathématique de la Société des Sciences Mathématiques de Roumanie 63 (2020), 43-49

  • -An observation on the determinant of a Sylvester-Kac type matrix} (with E. Kilic), Analele Universitatii Ovidius Constanta, Seria Matematica 28 (2020), 111-115

  • -A matrix approach to some second-order difference equations with sign-alternating coefficients (with M. Andelic, Z. Du, and E. Kilic), Journal of Difference Equations and Applications 26 (2020), 149-162

  • -The number of P-vertices of singular acyclic matrices: An inverse problem (with Z. Du), Discussiones Mathematicae Graph Theory 40 (2020), 525-532

Meet our team!