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%I #4 Dec 27 2017 15:39:30
%S 1,19,68,207,997,4210,16658,68769,284867,1170146,4807394,19787328,
%T 81424284,334903296,1377738399,5668140481,23317788357,95926011656,
%U 394630220291,1623463820564,6678736090662,27475550500449,113031264492453
%N Number of 4Xn 0..1 arrays with every 1 horizontally or antidiagonally adjacent to 1 neighboring 1s.
%C Row 4 of A297224.
%H R. H. Hardin, <a href="/A297226/b297226.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 4*a(n-2) +29*a(n-3) +66*a(n-4) +121*a(n-5) +83*a(n-6) -a(n-7) -205*a(n-8) -224*a(n-9) +30*a(n-10) +473*a(n-11) -96*a(n-12) -289*a(n-13) -109*a(n-14) -3*a(n-15) +126*a(n-16) +160*a(n-17) -150*a(n-18) -112*a(n-19) +43*a(n-20) +124*a(n-21) -53*a(n-22) +3*a(n-23) -25*a(n-24) +6*a(n-25) -a(n-26) +a(n-27)
%e Some solutions for n=7
%e ..0..1..0..1..0..0..0. .0..0..0..0..0..0..0. .1..1..0..0..1..1..0
%e ..1..0..1..0..0..0..0. .0..0..0..0..0..0..0. .0..0..0..0..0..0..0
%e ..0..0..0..0..0..0..1. .0..0..1..1..0..0..0. .0..0..1..1..0..1..1
%e ..0..0..1..1..0..1..0. .0..0..0..0..0..0..0. .0..0..0..0..0..0..0
%Y Cf. A297224.
%K nonn
%O 1,2
%A _R. H. Hardin_, Dec 27 2017