Mathematical Proceedings of the Cambridge Philosophical Society

Research Article

The 2-variable polynomial of cable knots

H. R. Mortona1 and H. B. Shorta1

a1 Department of Pure Mathematics, University of Liverpool, Liverpool L69 3BX


The 2-variable polynomial PK of a satellite K is shown not to satisfy any formula, relating it to the polynomial of its companion and of the pattern, which is at all similar to the formulae for Alexander polynomials. Examples are given of various pairs of knots which can be distinguished by calculating P for 2-strand cables about them even though the knots themselves share the same P. Properties of a given knot such as braid index and amphicheirality, which may not be apparent from the knot's polynomial P, are shown in certain cases to be detectable from the polynomial of a 2-cable about the knot.

(Received February 24 1986)