Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I M1850 #19 Oct 21 2023 20:00:26
%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), 21-27.
%H Sean A. Irvine, <a href="/A003304/a003304.pdf">Illustration of initial terms</a>.
%K nonn,more
%O 2,1
%A _N. J. A. Sloane_
%E a(9)-a(12) from _Sean A. Irvine_, Mar 20 2017