Order theory | Lemmas | Wellfoundedness

Higman's lemma

In mathematics, Higman's lemma states that the set of finite sequences over a finite alphabet, as partially ordered by the subsequence relation, is well-quasi-ordered. That is, if is an infinite sequence of words over some fixed finite alphabet, then there exist indices such that can be obtained from by deleting some (possibly none) symbols. More generally this remains true when the alphabet is not necessarily finite, but is itself well-quasi-ordered, and the subsequence relation allows the replacement of symbols by earlier symbols in the well-quasi-ordering of labels. This is a special case of the later Kruskal's tree theorem. It is named after Graham Higman, who published it in 1952. (Wikipedia).

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Proof of Lemma and Lagrange's Theorem

Please Subscribe here, thank you!!! https://goo.gl/JQ8Nys Proof of Lemma and Lagrange's Theorem. This video starts by proving that any two right cosets have the same cardinality. Then we prove Lagrange's Theorem which says that if H is a subgroup of a finite group G then the order of H div

From playlist Abstract Algebra

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From playlist Theory of numbers

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From playlist Course 4: Linear Algebra (Fall 2017)

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From playlist Algebra

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From playlist PROBABILISTIC METHODS IN NEGATIVE CURVATURE - 2023

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From playlist ℕumber Theory

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From playlist Summer of Math Exposition Youtube Videos

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From playlist Research Spotlight

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From playlist Global Noncommutative Geometry Seminar (Americas)

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From playlist Rings and modules

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From playlist Conférence « Géométrie arithmétique en l’honneur de Luc Illusie » - 5 mai 2021

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From playlist Talks of Mathematics Münster's reseachers

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Laurent Bartholdi - Imbeddings in groups of subexponential growth

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From playlist T1-2014 : Random walks and asymptopic geometry of groups.

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Andrzej Zuk: Spectra of ultra-discrete limits

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From playlist Analysis and its Applications

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Nicolás Matte Bon: Confined subgroups and high transitivity

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From playlist Dynamical Systems and Ordinary Differential Equations

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From playlist Mathematics

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From playlist Riemann Hypothesis

Related pages

Mathematics | Subsequence | Well-quasi-ordering | Kruskal's tree theorem | Reverse mathematics