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%I #4 Mar 14 2018 07:16:52
%S 4,18,52,148,440,1367,4297,13510,42216,131239,407238,1264321,3929780,
%T 12224311,38033755,118318333,367999398,1144440136,3559039439,
%U 11068454635,34423573923,107061087524,332971544913,1035570611253,3220697791617
%N Number of nX3 0..1 arrays with every element equal to 0, 1, 2, 4 or 5 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
%C Column 3 of A300881.
%H R. H. Hardin, <a href="/A300876/b300876.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 7*a(n-1) -15*a(n-2) +44*a(n-4) -42*a(n-5) -42*a(n-6) +45*a(n-7) +44*a(n-8) -3*a(n-9) -15*a(n-10) -49*a(n-11) -52*a(n-12) -26*a(n-13) +86*a(n-14) +194*a(n-15) +84*a(n-16) +42*a(n-17) -92*a(n-18) -76*a(n-19) -43*a(n-20) -a(n-21) +13*a(n-22) +4*a(n-23) +3*a(n-24) -a(n-25) for n>26
%e Some solutions for n=5
%e ..0..1..0. .0..0..1. .0..0..0. .0..0..1. .0..1..1. .0..1..0. .0..1..0
%e ..0..1..1. .0..1..0. .1..1..0. .1..0..0. .1..0..1. .0..1..0. .0..1..1
%e ..0..0..1. .1..0..1. .0..1..1. .1..1..1. .1..0..0. .0..1..1. .1..1..0
%e ..1..0..1. .0..1..0. .1..1..0. .0..0..1. .1..1..1. .1..1..0. .0..1..0
%e ..1..0..1. .0..0..1. .0..1..1. .1..0..0. .0..0..0. .0..1..1. .0..1..0
%Y Cf. A300881.
%K nonn
%O 1,1
%A _R. H. Hardin_, Mar 14 2018
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