Sequence system: Difference between revisions

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(Created page with "A '''sequence system''' is an ordinal notation system in which sequences are well-ordered. Typically, it is an expansion system, with the expansion chosen so that x[n] is always lexicographically smaller than x, and additionally, so that x[0] is x without its last element and x[n] is always a subsequence of x[n+1]. If all of these hold, then as long as the base of its standard form is totally ordered, the order of the sequence system is identical to the lexicogr...")
 
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A '''sequence system''' is an [[ordinal notation system]] in which sequences are well-ordered.
A '''sequence system''' is an [[ordinal notation system]] in which sequences are well-ordered.


Typically, it is an [[expansion system]], with the expansion chosen so that x[n] is always lexicographically smaller than x, and additionally, so that x[0] is x without its last element and x[n] is always a subsequence of x[n+1]. If all of these hold, then as long as the base of its standard form is totally ordered, the order of the sequence system is identical to the lexicographical order.<ref>Generalization of the proof of lemma 2.3 in the [https://arxiv.org/abs/2307.04606 proof of well-foundedness] of [[Bashicu matrix system | BMS]]</ref>
Typically, it is an [[expansion system]], with the expansion chosen so that \( x[n] \) is always lexicographically smaller than \( x \), and additionally, so that \( x[0] \) is \( x \) without its last element and \( x[n] \) is always a subsequence of \( x[n+1] \). If all of these hold, then as long as the base of its standard form is totally ordered, the order of the sequence system is identical to the lexicographical order.<ref>Generalization of the proof of lemma 2.3 in the [https://arxiv.org/abs/2307.04606 proof of well-foundedness] of [[Bashicu matrix system | BMS]]</ref>


Notable sequence systems include [[Primitive sequence system]], [[Pair sequence system]], [[Sudden sequence system]], [[Bashicu matrix system]] and [[Y sequence]].
Notable sequence systems include [[Primitive sequence system]], [[Pair sequence system]], [[Sudden sequence system]], [[Bashicu matrix system]] and [[Y sequence]].

Revision as of 04:35, 11 July 2023

A sequence system is an ordinal notation system in which sequences are well-ordered.

Typically, it is an expansion system, with the expansion chosen so that \( x[n] \) is always lexicographically smaller than \( x \), and additionally, so that \( x[0] \) is \( x \) without its last element and \( x[n] \) is always a subsequence of \( x[n+1] \). If all of these hold, then as long as the base of its standard form is totally ordered, the order of the sequence system is identical to the lexicographical order.[1]

Notable sequence systems include Primitive sequence system, Pair sequence system, Sudden sequence system, Bashicu matrix system and Y sequence.

  1. Generalization of the proof of lemma 2.3 in the proof of well-foundedness of BMS