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%I #11 Jun 30 2023 10:26:49
%S 2,12,2144,9277152,934520913216,2152453777211211412,
%T 112252999240982874562527216,131765033045251672652319572331061144,
%U 3467852755777932367855581588111341658695967892
%N a(n) = A143246(2n).
%H Ed Wynn, <a href="http://arxiv.org/abs/1402.0545">Enumeration of nonisomorphic Hamiltonian cycles on square grid graphs</a>, arXiv preprint arXiv:1402.0545 [math.CO], 2014.
%H <a href="/index/Gra#graphs">Index entries for sequences related to graphs, Hamiltonian</a>
%K nonn
%O 1,1
%A _N. J. A. Sloane_, Feb 08 2013