File:Trefoil-triquetra-rhodonea-rose-limacon.png

Trefoil knot generated from the polar coordinates equation r=b+sin(aθ), which is a slight generalization of the Limaçon and Rose/rhodonea curves, using parameters a=(3/5) and b=(8/5). For a similar looking visual rendering of the 3_1 knot, but made from three 300° circular arcs, see image Image:Trefoil-Triquetra.png.

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

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