Category:Definitions/Orderings on Integers

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This category contains definitions related to Orderings on Integers.
Related results can be found in Category:Orderings on Integers.


Definition 1

The integers are ordered on the relation $\le$ as follows:

$\forall x, y \in \Z: x \le y$

if and only if:

$\exists c \in P: x + c = y$

where $P$ is the set of positive integers.


That is, $x$ is less than or equal to $y$ if and only if $y - x$ is non-negative.


Definition 2

The integers are ordered on the relation $\le$ as follows:

Let $x$ and $y$ be defined as from the formal definition of integers:

$x = \eqclass {x_1, x_2} {}$ and $y = \eqclass {y_1, y_2} {}$ where $x_1, x_2, y_1, y_2 \in \N$.


Then:

$x < y \iff x_1 + y_2 \le x_2 + y_1$

where:

$+$ denotes natural number addition
$\le$ denotes natural number ordering.