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A067963 Number of binary arrangements without adjacent 1's on n X n array connected e-w ne-sw nw-se.

%I A067963 #21 Aug 22 2016 16:52:56
%S A067963 2,7,77,1152,56549,3837761,806190208,251170142257,223733272186825,
%T A067963 319544298135448960,1210302996752248488817,7876274672755293629849313,
%U A067963 127662922218147601317696761088,3758866349549535184419575245899295
%N A067963 Number of binary arrangements without adjacent 1's on n X n array connected e-w ne-sw nw-se.
%H A067963 R. H. Hardin and Vaclav Kotesovec, <a href="/A067963/b067963.txt">Table of n, a(n) for n = 1..30</a>
%H A067963 V. Kotesovec, <a href="https://oeis.org/wiki/User:Vaclav_Kotesovec">Non-attacking chess pieces</a>, 6ed, 2013, p. 69-71.
%e A067963 Neighbors for n=4 (dots represent spaces):
%e A067963 . o--o--o--o
%e A067963 ...\/ \/ \/
%e A067963 .../\ /\ /\
%e A067963 . o--o--o--o
%e A067963 ...\/ \/ \/
%e A067963 .../\ /\ /\
%e A067963 . o--o--o--o
%e A067963 ...\/ \/ \/
%e A067963 .../\ /\ /\
%e A067963 . o--o--o--o
%Y A067963 Cf. circle A000204, line A000045, arrays: ne-sw nw-se A067965, n-s nw-se A067964, e-w n-s nw-se A066864, e-w ne-sw n-s nw-se A063443, n-s A067966, e-w n-s A006506, nw-se A067962, toruses: bare A002416, ne-sw nw-se A067960, ne-sw n-s nw-se A067959, e-w ne-sw n-s nw-se A067958, n-s A067961, e-w n-s A027683, e-w ne-sw n-s A066866.
%Y A067963 Diagonal of A228683
%K A067963 nonn,nice,hard
%O A067963 1,1
%A A067963 _R. H. Hardin_, Feb 02 2002
%E A067963 Terms a(15)-a(19) from _Vaclav Kotesovec_, May 01 2012