A knot without tritangent planes
It is shown that a certain \((3,2)\)-curve on a torus of revolution with radii \(1:1.2\) has no tritangent planes. A different example has been obtained by \textit{H. Morton} in [Bull. Lond. Math. Soc. 23, 78--80 (1991; Zbl 0726.53003), see the following review].
scientific article; zbMATH DE number 4198931