

Combinatorics
Combinatorics is the branch of mathematics studying the enumeration,combination, andpermutation ofsets of elements and the mathematical relations that characterize their properties.
Mathematicians sometimes use the term "combinatorics" to refer to a larger subset ofdiscrete mathematics that includesgraph theory. In that case, what is commonly called combinatorics is then referred to as "enumeration."
The Season 1 episode "Noisy Edge" (2005) of the television crime dramaNUMB3RS mentions combinatorics.
See also
Algebraic Combinatorics,Antichain,Chain,Concrete Mathematics,Dilworth's Lemma,Dirichlet's Box Principle,Discrete Mathematics,Enumeration Problem,Erdős-Szekeres Theorem,Inclusion-Exclusion Principle,Kirkman's Schoolgirl Problem,Kirkman Triple System,Partial Order,Partial Order Length,Partial Order Width,Ramsey's Theorem,Schröder-Bernstein Theorem,Schur's Lemma,Sperner's Theorem,Total Order,Umbral Calculus,van der Waerden's TheoremExplore this topic in the MathWorld classroomExplore with Wolfram|Alpha

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References
Abramowitz, M. and Stegun, I. A. (Eds.). "Combinatorial Analysis." Ch. 24 inHandbook of Mathematical Functions with Formulas, Graphs, and Mathematical Tables, 9th printing. New York: Dover, pp. 821-827, 1972.Aigner, M.Combinatorial Theory. New York: Springer-Verlag, 1997.Balakrishnan, V. K.Schaum's Outline of Combinatorics, including Concepts of Graph Theory. New York: McGraw-Hill, 1995.Bellman, R. and Hall, M.Combinatorial Analysis. Amer. Math. Soc., 1979.Berge, C.Principles of Combinatorics. New York: Academic Press, 1971.Bergeron, F.; Labelle, G.; and Leroux, P.Combinatorial Species and Tree-Like Structures. Cambridge, England: Cambridge University Press, 1998.Biggs, N. L. "The Roots of Combinatorics."Historia Mathematica6, 109-136, 1979.Bose, R. C. and Manvel, B.Introduction to Combinatorial Theory. New York: Wiley, 1984.Cameron, P. J.Combinatorics: Topics, Techniques, Algorithms. New York: Cambridge University Press, 1994.Cohen, D.Basic Techniques of Combinatorial Theory. New York: Wiley, 1978.Cohen, D. E.Combinatorial Group Theory: A Topological Approach. New York: Cambridge University Press, 1989.Colbourn, C. J. and Dinitz, J. H. (Eds.).CRC Handbook of Combinatorial Designs. Boca Raton, FL: CRC Press, 1996.MathPages. "Combinatorics."http://www.mathpages.com/home/icombina.htm.Comtet, L.Advanced Combinatorics: The Art of Finite and Infinite Expansions, rev. enl. ed. Dordrecht, Netherlands: Reidel, 1974.
Referenced on Wolfram|Alpha
CombinatoricsCite this as:
Weisstein, Eric W. "Combinatorics." FromMathWorld--A Wolfram Resource.https://mathworld.wolfram.com/Combinatorics.html