%I M1850
%S 2,8,32,144,708,3696,20296,115624,676828,4044744,24565432
%N Number of figure 8's with 2n edges on the square lattice.
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%D S. G. Whittington and J. P. Valleau, Figure eights on the square lattice: enumeration and Monte Carlo estimation, J. Phys. A 3 (1970), 2127.
%H Sean A. Irvine, <a href="/A003304/a003304.pdf">Illustration of initial terms</a>
%K nonn
%O 2,1
%A _N. J. A. Sloane_.
%E a(9)a(12) from _Sean A. Irvine_, Mar 20 2017
