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%I #7 Feb 21 2019 11:36:29
%S 4,16,49,161,548,1824,6081,20353,68036,227376,760145,2541153,8494692,
%T 28397120,94929633,317342017,1060849668,3546339664,11855139953,
%U 39630819361,132482782884,442879752544,1480512941569,4949240890113
%N Number of 2 X n 0..1 arrays with no 1 equal to more than two of its horizontal, diagonal and antidiagonal neighbors.
%H R. H. Hardin, <a href="/A283692/b283692.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 3*a(n-1) + a(n-2) + 3*a(n-3) - 6*a(n-4) - 8*a(n-5).
%F Empirical g.f.: x*(4 + 4*x - 3*x^2 - 14*x^3 - 8*x^4) / ((1 + x + 2*x^2)*(1 - 4*x + x^2 + 4*x^3)). - _Colin Barker_, Feb 21 2019
%e Some solutions for n=4:
%e ..0..0..1..0. .1..0..0..1. .1..1..0..1. .0..0..0..0. .0..0..0..1
%e ..0..0..0..0. .0..0..1..0. .0..1..0..1. .0..0..1..1. .0..1..0..1
%Y Row 2 of A283691.
%K nonn
%O 1,1
%A _R. H. Hardin_, Mar 14 2017
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