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%I #4 Nov 12 2017 20:02:18
%S 7,87,741,6686,59126,528282,4738235,42321441,378112132,3379951089,
%T 30211913537,270034246073,2413553512560,21572510872955,
%U 192816992434886,1723410496604699,15403947766639408,137681484497162534
%N Number of nX4 0..1 arrays with each 1 horizontally or vertically adjacent to 1 or 2 1s.
%C Column 4 of A295040.
%H R. H. Hardin, <a href="/A295036/b295036.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 6*a(n-1) +11*a(n-2) +110*a(n-3) +218*a(n-4) +381*a(n-5) -1782*a(n-6) -2295*a(n-7) +4944*a(n-8) +5724*a(n-9) -6097*a(n-10) -7938*a(n-11) -1252*a(n-12) +14108*a(n-13) +11254*a(n-14) -22229*a(n-15) -16840*a(n-16) +27235*a(n-17) -25020*a(n-18) +11308*a(n-19) +6762*a(n-20) -1639*a(n-21) +2585*a(n-22) +642*a(n-23) -2303*a(n-24) -429*a(n-25) +661*a(n-26) -215*a(n-27) +117*a(n-28) -14*a(n-29) -36*a(n-30) +7*a(n-31) +4*a(n-32) +2*a(n-33) -a(n-34)
%e Some solutions for n=5
%e ..0..1..1..0. .1..0..1..0. .0..0..1..0. .0..1..0..1. .1..0..0..0
%e ..1..0..1..0. .1..0..1..0. .0..0..1..0. .0..1..0..1. .1..0..0..0
%e ..1..0..1..1. .1..0..0..0. .0..0..0..0. .1..0..0..0. .1..0..0..0
%e ..0..0..0..1. .1..0..0..0. .0..0..0..1. .1..0..1..0. .1..0..0..0
%e ..1..1..0..0. .0..1..1..1. .0..0..1..1. .1..1..1..0. .1..1..0..0
%Y Cf. A295040.
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 12 2017
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