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%I #4 Nov 20 2017 12:18:49
%S 5,20,76,299,1198,4775,19214,77650,314916,1281050,5224082,21344769,
%T 87348360,357898094,1467894633,6025215866,24746954977,101691771957,
%U 418041974157,1719049438541,7070709945652,29088512708512,119686780663978
%N Number of nX3 0..1 arrays with each 1 horizontally or vertically adjacent to 0, 2 or 3 1s.
%C Column 3 of A295352.
%H R. H. Hardin, <a href="/A295347/b295347.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 6*a(n-1) -4*a(n-2) -13*a(n-3) -8*a(n-4) -17*a(n-5) +35*a(n-6) -14*a(n-7) +43*a(n-8) +48*a(n-9) -41*a(n-10) +43*a(n-11) -25*a(n-12) -5*a(n-13) -18*a(n-14) -a(n-15) +2*a(n-16) +a(n-17) +a(n-18)
%e Some solutions for n=5
%e ..1..0..1. .1..1..0. .0..0..1. .0..1..0. .1..0..0. .0..1..1. .1..0..0
%e ..0..0..0. .1..1..0. .0..0..0. .1..0..1. .0..0..0. .1..1..1. .0..0..0
%e ..1..0..0. .0..0..0. .0..0..0. .0..0..0. .0..0..0. .1..0..1. .0..0..0
%e ..0..1..0. .1..1..0. .1..0..0. .0..0..0. .0..0..0. .1..1..1. .0..0..0
%e ..0..0..1. .1..1..0. .0..0..1. .1..0..1. .1..0..1. .1..1..1. .0..1..0
%Y Cf. A295352.
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 20 2017