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%I #4 Mar 29 2018 12:59:22
%S 5,9,25,64,169,441,1156,3025,7921,20736,54289,142129,372100,974169,
%T 2550409,6677056,17480761,45765225,119814916,313679521,821223649,
%U 2149991424,5628750625,14736260449,38580030724,101003831721,264431464441
%N Number of nX4 0..1 arrays with every element equal to 0, 1 or 4 horizontally or antidiagonally adjacent elements, with upper left element zero.
%C Column 4 of A301964.
%H R. H. Hardin, <a href="/A301960/b301960.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 2*a(n-1) +2*a(n-2) -a(n-3) for n>4
%e Some solutions for n=5
%e ..0..0..1..0. .0..1..1..0. .0..0..1..0. .0..1..0..1. .0..1..0..1
%e ..1..1..1..0. .0..0..1..0. .1..1..1..0. .0..1..1..1. .0..1..0..1
%e ..1..0..1..0. .1..0..1..0. .1..0..1..1. .0..1..0..1. .1..0..1..0
%e ..1..0..0..0. .1..0..1..0. .1..0..0..1. .0..0..0..1. .1..0..1..1
%e ..1..0..1..1. .1..0..1..0. .1..1..0..0. .0..1..0..0. .1..0..0..1
%Y Cf. A301964.
%K nonn
%O 1,1
%A _R. H. Hardin_, Mar 29 2018
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