A067646 - OEIS

%I #12 Jul 12 2020 14:17:49

%S 1,2,4,8,24,72,264,1074,4490,20296,92768,439148,2118654,10377708,

%T 51740280,260545092,1328891356,6836872181

%N Number of prime alternating tangles (or knots) with two connected components.

%H S. R. Finch, <a href="http://www.people.fas.harvard.edu/~sfinch/">Knots, links and tangles</a>

%H S. R. Finch, <a href="/A002863/a002863_4.pdf">Knots, links and tangles</a>, Aug 08 2003. [Cached copy, with permission of the author]

%H J. L. Jacobsen and P. Zinn-Justin, <a href="http://arXiv.org/abs/math-ph/0102015">A Transfer Matrix approach to the Enumeration of Knots</a>

%Y Equals A067644 + 2*A067645.

%K nonn

%O 0,2

%A _N. J. A. Sloane_, Feb 05 2002

%E More terms from Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Apr 21 2003