4-loop Brunnian link — no two loops are directly linked, but all four are collectively linked, and cutting any loop frees all the other loops.
AnonMoos
<p>Redrawn version of illustration in Hermann Brunn's 1892 article "Über Verkettung", by way of Dale Rolfsen's 1976 book <i>Knots and Links</i> (p. 67).
</p><p>SVG version of <a href="//commons.wikimedia.org/wiki/File:Brunnian.png" title="File:Brunnian.png">Image:Brunnian.png</a> .  Converted from the following PostScript code:
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