翻訳と辞書 Words near each other ・ Welleritidae ・ Wellerlooi ・ Wellersburg, Pennsylvania ・ Welles ・ Welles (name) ・ Welles Crowther ・ Welles Declaration ・ Welles House ・ Welles House, Wilkes Barre Pennsylvania ・ Welles-Pérennes ・ Well-order ・ Well-ordering principle ・ Well-ordering theorem ・ Well-pointed category ・ Well-posed problem ・ Well-quasi-ordering ・ Well-Schooled in Murder ・ Well-separated pair decomposition ・ Well-structured transition system ・ Well-Tech Award ・ Well-tempered ・ Well-Tempered Clavicle ・ Well-woman examination ・ Well... ・ Wella ・ Wellacre Academy ・ Wellacre Quarry ・ Wellagiriya ・ Wellan's ・ Welland Dictionary Lists mini英和辞書 mini和英辞書 Webster 1913 Latin-English FOLDOC Wikipedia English ウィキペディア

翻訳と辞書　辞書検索 [ 開発暫定版 ] スポンサード リンク Well-quasi-ordering ： ウィキペディア英語版 Well-quasi-ordering In mathematics, specifically order theory, a well-quasi-ordering or wqo is a quasi-ordering such that any infinite sequence of elements $x\_0$, $x\_1$, $x\_2$, … from $X$ contains an increasing pair $x\_i\backslash le\; x\_j$ with == Motivation == Well-founded induction can be used on any set with a well-founded relation, thus one is interested in when a quasi-order is well-founded. However the class of well-founded quasiorders is not closed under certain operations - that is, when a quasi-order is used to obtain a new quasi-order on a set of structures derived from our original set, this quasiorder is found to be not well-founded. By placing stronger restrictions on the original well-founded quasiordering one can hope to ensure that our derived quasiorderings are still well-founded. An example of this is the power set operation. Given a quasiordering $\backslash le$ for a set $X$ one can define a quasiorder $\backslash le^$ on $X$'s power set $P(X)$ by setting $A\; \backslash le^\; B$ if and only if for each element of $A$ one can find some element of $B$ which is larger than it under $\backslash le$. One can show that this quasiordering on $P(X)$ needn't be well-founded, but if one takes the original quasi-ordering to be a well-quasi-ordering, then it is. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Well-quasi-ordering」の詳細全文を読む スポンサード リンク 翻訳と辞書 : 翻訳のためのインターネットリソース Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.