Figure 3.

Correlation between the computed 3D writhe of the ideal configuration of alternating knots and links (Wr) and the predicted value (PWr). Alternating knots up to eight crossings are indicated by an open diamond (Wr data from ref. 5), and alternating two-component links up to four crossings are indicated by a filled diamond (Wr data provided by Ben Laurie, personal communication). It is to be observed that the PWr of knots are multiples of 4/7 (vertical dotted lines) and that the PWr of two-component links are equal to 2/7 plus multiples of 4/7 (between two vertical dotted lines).