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%I #8 Jan 15 2019 09:11:04
%S 13,65,316,1462,6383,27531,115391,478849,1957904,7940136,31916445,
%T 127480373,506131101,1999695453,7865869056,30823236470,120372357259,
%U 468663337303,1819741296607,7048393305965,27239539562644,105056982554032
%N Number of n X 4 binary arrays with some element plus some horizontally, vertically, diagonally or antidiagonally adjacent neighbor totalling two no more than once.
%H R. H. Hardin, <a href="/A268777/b268777.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 4*a(n-1) + 10*a(n-2) - 32*a(n-3) - 47*a(n-4) + 40*a(n-5) + 38*a(n-6) - 12*a(n-7) - 9*a(n-8).
%F Empirical g.f.: x*(13 + 13*x - 74*x^2 - 36*x^3 + 66*x^4 + 26*x^5 - 21*x^6 - 9*x^7) / (1 - 2*x - 7*x^2 + 2*x^3 + 3*x^4)^2. - _Colin Barker_, Jan 15 2019
%e Some solutions for n=4:
%e ..0..0..0..0. .1..0..0..0. .0..1..0..0. .1..0..1..0. .0..0..0..1
%e ..1..0..1..0. .0..0..0..1. .1..0..0..0. .0..0..0..0. .1..0..0..0
%e ..0..0..1..0. .1..0..0..0. .0..0..0..0. .0..0..1..0. .1..0..0..0
%e ..1..0..0..0. .1..0..1..0. .1..0..0..0. .1..0..0..1. .0..0..0..1
%Y Column 4 of A268781.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 13 2016
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