|> To me it seems math people usually exclude zero
Math people changed their mind, but for historical reasons there is some confusion.¹
Natural numbers are defined by successively adding 1 and zero is the neutral element of addition.
It's much easier to operate on sets with neutral element included!
Most integer operations (at least in Perl) can return 0.
Thats the meta-argument why Moritz's answer makes perfect sense. This way combinations of integer functions always include another neutral element as possible result.
For instance otherwise adding the sum of the first index of two arrays would be 2 (the second element) instead of 0 (again the first)
( addicted to the Perl Programming Language)
1) the concept of natural numbers was older than group theory
Are you posting in the right place? Check out Where do I post X? to know for sure.
Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
<code> <a> <b> <big>
<blockquote> <br /> <dd>
<dl> <dt> <em> <font>
<h1> <h2> <h3> <h4>
<h5> <h6> <hr /> <i>
<li> <nbsp> <ol> <p>
<small> <strike> <strong>
<sub> <sup> <table>
<td> <th> <tr> <tt>
Snippets of code should be wrapped in
<code> tags not
<pre> tags. In fact, <pre>
tags should generally be avoided. If they must
be used, extreme care should be
taken to ensure that their contents do not
have long lines (<70 chars), in order to prevent
horizontal scrolling (and possible janitor
Want more info? How to link
or How to display code and escape characters
are good places to start.