In
mathematics, the Milliken–Taylor theorem in
combinatorics
Combinatorics is an area of mathematics primarily concerned with counting, both as a means and an end in obtaining results, and certain properties of finite structures. It is closely related to many other areas of mathematics and has many a ...
is a generalization of both
Ramsey's theorem
In combinatorics, Ramsey's theorem, in one of its graph-theoretic forms, states that one will find monochromatic cliques in any edge labelling (with colours) of a sufficiently large complete graph. To demonstrate the theorem for two colours (s ...
and
Hindman's theorem
In mathematics, an IP set is a set of natural numbers which contains all finite sums of some infinite set.
The finite sums of a set ''D'' of natural numbers are all those numbers that can be obtained by adding up the elements of some finite non-e ...
. It is named after Keith Milliken and
Alan D. Taylor.
Let
denote the set of finite subsets of
, and define a partial order on
by α<β
if and only if
In logic and related fields such as mathematics and philosophy, "if and only if" (shortened as "iff") is a biconditional logical connective between statements, where either both statements are true or both are false.
The connective is bi ...
max α
\langle a_n \rangle_^\infty \subset \mathbb and , let
:
Let denote the ''k''-element subsets of a set ''S''. The Milliken–Taylor theorem says that for any finite partition , there exist some and a sequence such that .
For each , call an ''MTk set''. Then, alternatively, the Milliken–Taylor theorem asserts that the collection of MT''k'' sets is partition regular
In combinatorics, a branch of mathematics, partition regularity is one notion of largeness for a collection of sets.
Given a set X, a collection of subsets \mathbb \subset \mathcal(X) is called ''partition regular'' if every set ''A'' in the coll ...
for each ''k''.
References
*.
*.
Ramsey theory
Theorems in discrete mathematics
{{combin-stub