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A268882 Number of n X 4 binary arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling two exactly once.

%I A268882 #7 Jan 15 2019 14:41:50
%S A268882 5,54,501,4133,31956,236960,1706732,12034000,83485488,571836176,
%T A268882 3876692480,26059576704,173934499008,1153927868416,7615733792000,
%U A268882 50035609197824,327432063642624,2135189929320448,13880060602788864
%N A268882 Number of n X 4 binary arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling two exactly once.
%H A268882 R. H. Hardin, <a href="/A268882/b268882.txt">Table of n, a(n) for n = 1..210</a>
%F A268882 Empirical: a(n) = 16*a(n-1) - 88*a(n-2) + 200*a(n-3) - 208*a(n-4) + 96*a(n-5) - 16*a(n-6) for n>7.
%F A268882 Empirical g.f.: x*(5 - 26*x + 77*x^2 - 131*x^3 + 156*x^4 - 80*x^5 + 4*x^6) / (1 - 8*x + 12*x^2 - 4*x^3)^2. - _Colin Barker_, Jan 15 2019
%e A268882 Some solutions for n=4:
%e A268882 ..1..0..1..0. .0..1..0..1. .0..0..0..1. .0..0..0..0. .0..1..0..0
%e A268882 ..1..0..1..0. .0..0..0..0. .0..1..0..1. .0..1..1..0. .1..0..1..0
%e A268882 ..0..0..1..0. .0..0..0..1. .0..0..0..1. .0..0..0..0. .0..0..0..1
%e A268882 ..0..1..0..0. .0..0..1..0. .1..0..1..0. .1..0..1..0. .0..0..0..0
%Y A268882 Column 4 of A268886.
%K A268882 nonn
%O A268882 1,1
%A A268882 _R. H. Hardin_, Feb 15 2016