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%I #8 Jul 02 2018 04:53:24
%S 14,982,71956,5269968,385979024,28269518640,2070490270512,
%T 151644956050096,11106641282635568,813462470412951472,
%U 59578874831184784432,4363621500998057092272,319596378043822928054576
%N Number of n X 4 0..2 arrays with new values 0..2 introduced in row major order and no element equal to more than two of its immediate leftward or upward or left-upward diagonal neighbors.
%C Column 4 of A208322.
%H R. H. Hardin, <a href="/A208318/b208318.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 65*a(n-1) + 600*a(n-2) + 320*a(n-3) - 4224*a(n-4) + 1728*a(n-5) for n>6.
%F Empirical g.f.: 2*x*(7 + 36*x - 137*x^2 - 426*x^3 + 1200*x^4 - 432*x^5) / (1 - 65*x - 600*x^2 - 320*x^3 + 4224*x^4 - 1728*x^5). - _Colin Barker_, Jul 02 2018
%e Some solutions for n=4:
%e ..0..1..1..0....0..0..0..1....0..0..0..1....0..0..0..0....0..0..0..0
%e ..1..2..1..2....2..0..1..0....1..1..1..0....1..0..1..0....0..1..1..0
%e ..0..1..2..1....0..2..1..1....0..1..2..2....2..2..1..2....0..1..0..2
%e ..2..0..0..1....2..0..0..1....0..0..0..2....0..0..2..0....2..2..0..1
%Y Cf. A208322.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 25 2012
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