<p><a href="https://en.wikiversity.org/wiki/Inversion_(discrete_mathematics)" class="extiw" title="v:Inversion (discrete mathematics)">v:Inversion (discrete mathematics)</a>
</p>
<table style="color:#000; background:#F8F9FA; border:1px solid #BAB;"><tbody><tr><td><a href="//commons.wikimedia.org/wiki/File:Inkscape_Logo.svg" class="image"><img alt="Inkscape Logo.svg" src="https://upload.wikimedia.org/wikipedia/commons/thumb/0/0d/Inkscape_Logo.svg/20px-Inkscape_Logo.svg.png" decoding="async" width="20" height="20" srcset="https://upload.wikimedia.org/wikipedia/commons/thumb/0/0d/Inkscape_Logo.svg/30px-Inkscape_Logo.svg.png 1.5x, https://upload.wikimedia.org/wikipedia/commons/thumb/0/0d/Inkscape_Logo.svg/40px-Inkscape_Logo.svg.png 2x" data-file-width="128" data-file-height="128"></a>
</td><td style="font-size:.85em; padding: 1px 5px;">This <a href="https://en.wikipedia.org/wiki/SVG" class="extiw" title="w:SVG">SVG</a> was created with <a href="https://en.wikipedia.org/wiki/Inkscape" class="extiw" title="w:Inkscape">Inkscape</a>.
</td></tr></tbody></table>
<table><tbody><tr><td style="padding: 15px;"><a href="//commons.wikimedia.org/wiki/File:Watchduck.svg" class="image"><img alt="Watchduck.svg" src="https://upload.wikimedia.org/wikipedia/commons/thumb/d/d8/Watchduck.svg/40px-Watchduck.svg.png" decoding="async" width="40" height="46" srcset="https://upload.wikimedia.org/wikipedia/commons/thumb/d/d8/Watchduck.svg/60px-Watchduck.svg.png 1.5x, https://upload.wikimedia.org/wikipedia/commons/thumb/d/d8/Watchduck.svg/80px-Watchduck.svg.png 2x" data-file-width="703" data-file-height="806"></a>
</td>
<td><a href="//commons.wikimedia.org/wiki/User:Watchduck" title="User:Watchduck">Watchduck</a><br><span style="color: gray; font-size: 80%;">You can name the author as "T. Piesk", "Tilman Piesk" or "Watchduck".</span>
</td></tr></tbody></table>
<span class="int-own-work" lang="en">Own work</span>