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%I #8 Feb 28 2019 18:34:30
%S 4,8,25,57,156,384,1009,2545,6580,16760,43081,110121,282444,722928,
%T 1852705,4744417,12155236,31132904,79753849,204285465,523300860,
%U 1340442720,3433646161,8795417041,22530001684,57711669848,147831676585
%N Number of 2 X n 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 0 or 2 neighboring 1s.
%H R. H. Hardin, <a href="/A297458/b297458.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) + 3*a(n-2) + a(n-3) + 4*a(n-4).
%F Empirical g.f.: x*(4 + 4*x + 5*x^2 + 4*x^3) / ((1 + x^2)*(1 - x - 4*x^2)). - _Colin Barker_, Feb 28 2019
%e Some solutions for n=7:
%e ..0..0..1..1..0..0..1. .0..0..1..1..0..0..0. .0..0..0..1..0..0..0
%e ..1..0..1..1..0..0..0. .0..0..1..1..0..1..0. .0..1..0..0..0..1..0
%Y Row 2 of A297457.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 30 2017
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