# GetWiki

*Successor function*

ARTICLE SUBJECTS

being →

database →

ethics →

fiction →

history →

internet →

language →

linux →

logic →

method →

news →

policy →

purpose →

religion →

science →

software →

truth →

unix →

wiki →

ARTICLE TYPES

essay →

feed →

help →

system →

wiki →

ARTICLE ORIGINS

critical →

forked →

imported →

original →

Successor function

[ temporary import ]

**please note:**

- the content below is remote from Wikipedia

- it has been imported raw for GetWiki

**successor function**or

**successor operation**is a primitive recursive function

*S*such that

*S*(

*n*) =

*n*+1 for each natural number

*n*.For example,

*S*(1) = 2 and

*S*(2) = 3. Successor operations are also known as

**zeration**in the context of a zeroth hyperoperation: H0(

*a*,

*b*) = 1 +

*b*. In this context, the extension of zeration is addition, which is defined as repeated succession.

## Overview

The successor function is used in the Peano axioms which define the natural numbers. As such, it is not defined by addition, but rather is used to define all natural numbers beyond 0, as well as addition. For example, 1 is defined to be*S*(0), and addition on natural numbers is defined recursively by:

{|

This can be used to compute addition of any two natural numbers. For example, 5 + 2 = 5 +

m + 0 >| = m |

m + S(n) >| = S(m) + n |

*S*(1) =*S*(5) + 1 = 6 + 1 = 6 +*S*(0) =*S*(6) + 0 = 7 + 0 = 7Several ways have been proposed to construct the natural numbers using set theory, see set-theoretic definition of natural numbers. A common approach is to define the number 0 to be the empty set {}, and the successor*S*(*x*) to be*x*âˆª {*x*}. The axiom of infinity then guarantees the existence of a set â„• that contains 0 and is closed with respect to*S*; members of â„• are called natural numbers.Halmos, Chapter 11The successor function is the level-0 foundation of the infinite Grzegorczyk hierarchy of hyperoperations, used to build addition, multiplication, exponentiation, tetration, etc.. It was studied in 1986 in an investigation involving generalization of the pattern for hyperoperations. This use gave rise to the term*zeration*.WEB, Rubtsov, C.A., Romerio, G.F., Ackermann's Function and New Arithmetical Operations, 2004,weblink The successor function is commutative,{{clarify|reason=Commutativity makes sense only for binary operations. However, the only binary operations mentioned here is H0, which is not commutative.|date=December 2018}} though it is not associative, unlike the next two hyperoperations.It is also one of the primitive functions used in the characterization of computability by recursive functions.## See also

## References

{{reflist}}- BOOK, Paul R. Halmos, Naive Set Theory, 1968, Nostrand,

**- content above as imported from Wikipedia**

- "

- time: 9:57pm EST - Fri, Jan 18 2019

- "

__Successor function__" does not exist on GetWiki (yet)- time: 9:57pm EST - Fri, Jan 18 2019

[ this remote article is provided by Wikipedia ]

LATEST EDITS [ see all ]

GETWIKI 09 MAY 2016

GETWIKI 18 OCT 2015

GETWIKI 20 AUG 2014

GETWIKI 19 AUG 2014

GETWIKI 18 AUG 2014

© 2019 M.R.M. PARROTT | ALL RIGHTS RESERVED