Content deleted Content added
m Graph (mathematics) is now a disambiguation link; please fix., replaced: graph → graph{{dn|{{subst:DATE}}}} using AWB |
m Fixing links to disambiguation pages, replaced: graph{{dn|date=January 2016}} → graph using AWB |
||
Line 1:
'''Extremal combinatorics''' is a field of [[combinatorics]], which is itself a part of [[mathematics]]. Extremal combinatorics studies how large or how small a collection of finite objects ([[number]]s, [[Graph (discrete mathematics)|graph]]
Much of extremal combinatorics concerns [[class (set theory)|class]]es of sets; this is called '''extremal set theory'''. For instance, in an ''n''-element set, what is the largest number of ''k''-element [[subset]]s that can pairwise intersect one another? What is the largest number of subsets of which none contains any other? The latter question is answered by [[Sperner family#Sperner's theorem|Sperner's theorem]], which gave rise to much of extremal set theory.
| |||