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%I #8 Oct 29 2018 05:03:34
%S 5,21,89,375,1583,6685,28241,119319,504151,2130189,9000729,38030999,
%T 160693343,678981661,2868918401,12122113399,51219871687,216420616013,
%U 914447487881,3863838035639,16325972308111,68982542575773
%N Number of 2 X n 0..3 arrays with no element equal to one plus the sum of elements to its left or three plus the sum of the elements above it or one plus the sum of the elements diagonally to its northwest, modulo 4.
%H R. H. Hardin, <a href="/A240461/b240461.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 6*a(n-1) - 7*a(n-2) - 4*a(n-3) + 8*a(n-4).
%F Empirical g.f.: x*(5 - 9*x - 2*x^2 + 8*x^3) / (1 - 6*x + 7*x^2 + 4*x^3 - 8*x^4). - _Colin Barker_, Oct 29 2018
%e Some solutions for n=4:
%e ..2..2..2..0....0..2..0..2....0..2..0..2....2..2..2..0....0..0..0..0
%e ..2..2..2..0....0..3..1..3....0..0..2..0....2..2..2..1....2..2..0..0
%Y Row 2 of A240460.
%K nonn
%O 1,1
%A _R. H. Hardin_, Apr 05 2014
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