File:Trefoil-square.png

Square depiction of 3_1 knot. For a similar but more complex visual representation of a knot, see Image:10crossings square.png.

Self-made, declared to be in public domain, generated from the following PostScript source code:

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exch}def/l{X lineto}def 0 3 X moveto 0 1 l 3 1 l 3 2 l 1 2 l
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72 setlinewidth 0 setgray 1.5 1 X moveto 1 0 r stroke
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1 setgray 36 setlinewidth 1.48 1 X moveto 1.04 0 r stroke
2 1.48 X moveto 0 1.04 r stroke 1 .48 X moveto 0 1.04 r stroke
showpage
%EOF