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%I #6 Jan 25 2022 21:05:15
%S 1,11,72,459,2956,18996,122043,784108,5037730,32366408,207947716,
%T 1336022660,8583679582,55148432350,354317698174,2276420668626,
%U 14625549576730,93966244187418,603714410892078,3878744894728494
%N Number of n X 3 0..1 arrays with every element equal to 1, 2, 3, 4 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
%C Column 3 of A300973.
%H R. H. Hardin, <a href="/A300968/b300968.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 7*a(n-1) -2*a(n-2) -11*a(n-3) -a(n-4) +10*a(n-5) +6*a(n-6) -4*a(n-7) -4*a(n-8) -2*a(n-9) for n>11.
%e Some solutions for n=5
%e ..0..1..1. .0..1..1. .0..0..0. .0..1..1. .0..0..1. .0..0..0. .0..1..1
%e ..0..1..1. .0..0..0. .0..1..1. .0..0..1. .0..1..1. .1..1..1. .0..1..1
%e ..0..0..1. .0..0..0. .1..0..0. .0..1..0. .1..0..0. .0..0..0. .1..0..0
%e ..0..1..0. .1..1..0. .0..1..0. .0..0..0. .0..1..0. .0..1..0. .0..0..1
%e ..1..0..0. .1..0..0. .1..0..0. .1..1..1. .0..1..1. .0..1..0. .0..1..1
%Y Cf. A300973.
%K nonn
%O 1,2
%A _R. H. Hardin_, Mar 17 2018
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