https://whystartat.xyz/api.php?action=feedcontributions&feedformat=atom&user=PeterrowlettWhy start at x, y, z - User contributions [en-gb]2026-05-25T03:37:04ZUser contributionsMediaWiki 1.39.0https://whystartat.xyz/index.php?title=Talk:Natural_numbers&diff=306Talk:Natural numbers2021-08-26T13:54:43Z<p>Peterrowlett: Noting potential further ambiguity</p>
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<div>[https://en.wikipedia.org/wiki/Integer Wikipedia] also gives \(\mathbb{Z}_+\) and \(\mathbb{Z}^>\) for "positive integers" and \(\mathbb{Z}^{0+}\) and \(\mathbb{Z}^\ge\) for "non-negative integers", but I don't know if these are used ambiguously in relation to 0.</div>Peterrowletthttps://whystartat.xyz/index.php?title=Natural_numbers&diff=305Natural numbers2021-08-26T13:51:12Z<p>Peterrowlett: Expanded to include Z+</p>
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<div>The set of natural numbers, usually written \(\mathbb{N}\), sometimes includes 0 and sometimes doesn't include 0.<br />
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Relatedly, the set of integers \(\mathbb{Z}\) contains a subset \(\mathbb{Z}^+\). Sometimes this is used to mean strictly positive integers and so doesn't contain 0 and sometimes it is used to mean non-negative integers and does contain 0. <br />
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Sometimes authors define \(\mathbb{N}\) and \(\mathbb{Z}^+\) as the same thing, either with or without zero. Sometimes authors define them differently such that \(\mathbb{N}\) contains zero and \(\mathbb{Z}^+\) does not, and sometimes authors define them differently such that \(\mathbb{N}\) does not contain zero and \(\mathbb{Z}^+\) does. <br />
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[[Category:Conflicting definitions]]</div>Peterrowlett