A067648 Number of knot diagrams of type 2PI with n crossings and two outgoing strings.

0, 2, 0, 2, 4, 12, 60, 226, 1076, 5156, 24984, 128548, 663040, 3514968, 18918792, 103123906, 569877652, 3180066004, 17921451960, 101842206548, 583109887600, 3361640932872, 19499226668816

Offset: 0

Author

N. J. A. Sloane, Feb 05 2002

Keywords

• nonn

Links

• J. L. Jacobsen and P. Zinn-Justin, A Transfer Matrix approach to the Enumeration of Knots

Crossrefs

Cf. A054993, A067647.

Extensions

Reference gives two further terms.