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%I #9 Mar 29 2018 06:28:57
%S 4,28,89,361,1620,6392,26243,109483,447624,1841540,7595029,31226203,
%T 128506736,529054684,2177033731,8959709123,36876424418,151764857870,
%U 624602187635,2570631663169,10579647127402,43541564503936
%N Number of n X 4 binary arrays with every 1 having exactly one king-move neighbor equal to 1.
%C Column 4 of A183442.
%H R. H. Hardin, <a href="/A183437/b183437.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = a(n-1) + 6*a(n-2) + 26*a(n-3) + 15*a(n-4) - 12*a(n-5) - 52*a(n-6) - 28*a(n-7) - 18*a(n-8) + 7*a(n-9).
%F Empirical g.f.: x*(4 + 24*x + 37*x^2 - 63*x^4 - 80*x^5 - 46*x^6 - 11*x^7 + 7*x^8) / (1 - x - 6*x^2 - 26*x^3 - 15*x^4 + 12*x^5 + 52*x^6 + 28*x^7 + 18*x^8 - 7*x^9). - _Colin Barker_, Mar 29 2018
%e Some solutions for 3 X 4:
%e ..0..0..0..0....1..0..1..0....0..0..1..0....0..1..0..1....0..0..0..0
%e ..0..0..1..0....1..0..1..0....1..0..1..0....0..1..0..1....1..0..1..0
%e ..0..0..1..0....0..0..0..0....1..0..0..0....0..0..0..0....1..0..1..0
%Y Cf. A183442.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 04 2011
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