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%I #4 Jan 02 2018 12:00:49
%S 4,8,29,69,200,552,1641,4685,13716,40248,119365,353541,1051472,
%T 3133592,9358769,27971501,83684604,250541896,750515501,2248981061,
%U 6741211928,20210867784,60604323641,181749073613,545104106532,1634992796824
%N Number of 2Xn 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 0, 2 or 3 neighboring 1s.
%C Row 2 of A297637.
%H R. H. Hardin, <a href="/A297638/b297638.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 3*a(n-1) +a(n-2) -a(n-3) +6*a(n-4) -28*a(n-5) -24*a(n-6)
%e Some solutions for n=7
%e ..0..1..1..0..1..1..1. .1..0..1..1..1..0..0. .1..1..0..0..1..0..0
%e ..1..1..0..0..1..1..0. .1..0..1..1..0..0..0. .1..1..1..1..1..1..0
%Y Cf. A297637.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 02 2018
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