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Viewing Version 2 of 'even number'
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Title of object: even number
Canonical Name: EvenNumber
Type: Definition

Created on: 2003-09-05 15:11:23
Modified on: 2003-09-05 17:09:26

Creator: matte
Modifier: matte
Author: matte

Classification: msc:03-00, msc:11-00
Defines: odd number, even integer, odd integer

Preamble:

% this is the default PlanetMath preamble. as your knowledge
% of TeX increases, you will probably want to edit this, but
% it should be fine as is for beginners.
% almost certainly you want these
\usepackage{amssymb}
\usepackage{amsmath}
\usepackage{amsfonts}
% used for TeXing text within eps files
%\usepackage{psfrag}
% need this for including graphics (\includegraphics)
%\usepackage{graphicx}
% for neatly defining theorems and propositions
%\usepackage{amsthm}
% making logically defined graphics
%\usepackage{xypic}
% there are many more packages, add them here as you need them
% define commands here
\newcommand{\sR}[0]{\mathbb{R}}
\newcommand{\sC}[0]{\mathbb{C}}
\newcommand{\sN}[0]{\mathbb{N}}
\newcommand{\sZ}[0]{\mathbb{Z}}
\renewcommand{\bibname}{References}
Content:

{\bf Definition} Suppose $k$ is an integer.
If there exists an integer $r$ such that $k=2r+1$, then $k$ is an {\bf odd number}.
If there exists an integer $r$ such that $k=2r$, then $k$ is an {\bf even number}.
The concept of even and odd numbers are most easily understood in
the binary base. Then the above definition simply states that even numbers end
with a $0$, and odd numbers end with a $1$.
Using induction, or the fundamental theorem of arithmetic, one can prove that
every integer is either even or odd.