IMI Interdisciplinary Mathematics InstituteCollege of Arts and Sciences

László Székely

  • Professor
  • Department of Mathematics
  • University of South Carolina


C.Sc. Mathematics Hungarian Academy of Sciences 1987
Ph.D. Mathematics Eötvös University, Budapest 1983
M.S. Mathematics Eötvös University, Budapest 1980


1996 – Present Professor Department of Mathematics, University of South Carolina
2005 – 2007 Interim Director Industrial Mathematics Institute, Univ. of South Carolina
2002 – 2003 Visiting Fellow National Center for Biotechnology Information, Bethesda MD
1994 – 1996 Director Institute of Mathematics I, Eötvös University, Budapest
1992 – 1993 Visiting Assoc. Professor University of New Mexico, Albuquerque
1991 – 1996 Senior Associate Professor Eötvös University, Budapest
1991 – 1992 Alexander von Humboldt Fellow Rheinische Friedrich-Wilhelms Universität, Institu für Ökonometrie und Operations Research, and Institut für Diskrete Mathematik, Bonn, Germany
1990 Visitor Memphis State University, TN
1988 – 1990 Visiting Assoc. Professor University of New Mexico, Albuquerque
1986 – 1987 Postdoctoral Fellow University of Auckland, New Zealand
1984 – 1991 Associate Professor Eötvös University, Budapest
1982 – 1984 Research Fellow József Attila University, Szeged


Research Interests

My primary research areas are combinatorics and graph theory, and their applications to geometry, computer science and biology. In particular:

  • Combinatorial geometry: Erdos type problems in geometry, density of sets without certain distances, maximum number of unit distances or minimum number of distinct distances in finite point sets, Szemeredi-Trotter type theorems;
  • Graph drawing: crossing numbers of graphs, applications of crossing numbers of graphs to discrete geometry, graph drawing algorithms on surfaces, books, etc., approximation algorithms for crossing number problems;
  • Phylogeny reconstruction: stochastic models of the evolution of biomolecular sequences, identifiability conditions for reconstructible past, polynomial time algorithms for phylogeny reconstruction, the length of biomolecular sequences necessary for phylogeny reconstruction for all methods and for particular methods, Fourier-Hadamard transform;
  • Discrete probability: stochastic models for biomolecular sequence evolution, derandomization of randomized algorithms for graph drawing, Lovasz Local Lemma;
  • Design and analysis of algorithms: algorithms for graph drawing, approximation algorithms for crossing number problems, algorithms for phylogeny reconstruction;
  • Combinatorial optimization: the multiway cut problem, integral uniform multicommodity flow problem;
  • Extremal problems (graphs and set systems): Erdos-Ko-Rado type theorems, Sperner and LYM type theorems, extremal graph theory

Current Projects

  • NSF DMS 1600811 "Extremal and Probabilistic Combinatorics with applications II," (2016-2019) investigates basic extremal problems and properties random structures, in particular extremal set theory and use of the Lovasz Local Lemma, and applications of discrete mathematics to phylogenetics, networks, and other areas of sciences.
  • NSF DMS 1743625 "NSF-CBMS Conference on Additive Combinatorics from a Geometric Viewpoint", conference to be held on USC Columbia campus, May 20-25, 2018.


Teaching Activities

Current Courses

On sabbatical leave.

Previous Courses

  • Math 122 - Calculus for Business Administration and Social Sciences
  • Math 141 - Calculus I
  • Math 142 - Calculus II
  • Math 241 - Vector Calculus
  • Math 374 - Discrete Structures
  • Math 570 - Discrete Optimization
  • Math 574 - Discrete Mathematics I
  • Math 774 - Discrete Mathematics
  • Math 775 - Discrete Mathematics II
  • Math 778B - Selected Topics: The Linear Algebra Method in Combinatorics


Honors and Other Special Scientific Recognition

  • "People’s Republic Scholar" 1978–79 and 1979–80
  • "Alexander von Humboldt Fellow", 1991–92, 2010
  • "Doctor of the Hungarian Academy of Sciences", 1998
  • "Russell Research Award", University of South Carolina, 2007
  • Elsevier "Top Cited Paper in Adv. Appl. Math. Award" 2010 (for the paper L. A. Szekely and Hua Wang, On subtrees of trees, Adv. Appl. Math. 34, (2005), 138-155.)


5 Selected Publications

  • H. Aydinian, E. Czabarka, L. A. Szekely, Mixed orthogonal arrays, k-dimensional M-part Sperner multi-familes and full multi-transversals, in: Information Theory, Combinatorics, and Search Theory (in Memory of Rudolph Ahlswede), eds. H. Aydinian, F. Cicalese, C. Deppe, Lecture Notes in Computer Science 7777, 2013, Springer-Verlag, 371-401.
  • M. A. Steel, L. A. Szekely, E. Mossel, Phylogenetic information complexity: is testing a tree easier than finding it? J. Theor. Biology 25(2009), 95-102.
  • P. L. Erdos, M. A. Steel, L. A. Szekely, and T. J. Warnow, A few logs suffice to build (almost) all trees I, Random Structures and Algorithms 14(1999)(2), 153-184.
  • L. A. Szekely, Crossing numbers and hard Erdos problems in discrete geometry, Combinatorics, Probability, and Computing 6(3)(1997), 353-358.
  • F. Shahrokhi, O. Sykora, L. A. Szekely and I. Vrto, The crossing number of a graph on a compact 2-manifold, Adv. Math. 123, (1996), 105-119.


IMI Preprints and Seminars

Go to the list of 26 preprints and 9 seminars by László Székely.


Curriculum Vitae

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