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%I #4 Mar 12 2017 14:36:57
%S 0,6,37,639,2875,21963,127635,693783,3852792,20064881,103580688,
%T 524492026,2611146243,12857829918,62584105607,301823257243,
%U 1443755263689,6855724802293,32346704566179,151738352019137,708116512419058
%N Number of 3Xn 0..1 arrays with no 1 equal to more than one of its horizontal, diagonal and antidiagonal neighbors, with the exception of exactly two elements.
%C Row 3 of A283634.
%H R. H. Hardin, <a href="/A283636/b283636.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 6*a(n-1) +9*a(n-2) -43*a(n-3) -213*a(n-4) +69*a(n-5) +946*a(n-6) +1929*a(n-7) +1017*a(n-8) +2204*a(n-9) +1875*a(n-10) +2487*a(n-11) -2529*a(n-12) +5073*a(n-13) -3762*a(n-14) +2255*a(n-15) -798*a(n-16) +132*a(n-17) -8*a(n-18)
%e Some solutions for n=4
%e ..0..0..0..0. .1..0..1..0. .1..0..1..1. .0..0..0..0. .1..0..0..1
%e ..1..1..1..1. .1..1..0..0. .1..1..0..0. .1..0..0..0. .0..1..1..0
%e ..0..0..0..0. .0..1..0..0. .0..0..0..1. .1..1..1..1. .0..1..0..1
%Y Cf. A283634.
%K nonn
%O 1,2
%A _R. H. Hardin_, Mar 12 2017
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