%I #4 Nov 18 2017 09:32:28
%S 13,106,948,8271,72745,638779,5611444,49287776,432936397,3802804497,
%T 33402966717,293403800602,2577190667088,22637440972719,
%U 198841998745267,1746581705515965,15341566059588032,134756735569827292
%N Number of nX4 0..1 arrays with each 1 horizontally or vertically adjacent to 0, 1 or 3 1s.
%C Column 4 of A295253.
%H R. H. Hardin, <a href="/A295249/b295249.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 7*a(n-1) +16*a(n-2) +2*a(n-3) -9*a(n-4) -281*a(n-5) -215*a(n-6) +333*a(n-7) +624*a(n-8) +748*a(n-9) -638*a(n-10) +498*a(n-11) +56*a(n-12) -1887*a(n-13) +1222*a(n-14) -1454*a(n-15) -1696*a(n-16) +333*a(n-17) -3287*a(n-18) +4186*a(n-19) -424*a(n-20) +705*a(n-21) +3178*a(n-22) -1682*a(n-23) +2095*a(n-24) -931*a(n-25) -217*a(n-26) +139*a(n-27) -419*a(n-28) +67*a(n-29) -192*a(n-30) -472*a(n-31) +216*a(n-32) -89*a(n-33) +194*a(n-34) +42*a(n-35) -6*a(n-36) -65*a(n-37) -63*a(n-38) -29*a(n-39) +6*a(n-40) +20*a(n-41) +12*a(n-42) +3*a(n-43) -2*a(n-44) -a(n-45)
%e Some solutions for n=5
%e ..0..0..1..0. .0..1..0..1. .1..0..1..0. .0..1..0..0. .0..0..0..1
%e ..0..1..0..0. .0..0..0..1. .1..0..1..1. .0..0..0..0. .1..0..0..0
%e ..0..0..0..0. .1..0..0..0. .0..0..1..0. .1..0..0..1. .0..1..0..1
%e ..1..0..1..0. .1..0..1..0. .0..0..0..1. .0..0..1..0. .0..0..0..0
%e ..0..1..1..1. .0..0..1..0. .0..0..0..0. .0..0..1..0. .0..0..0..1
%Y Cf. A295253.
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 18 2017
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