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A208265 Number of n X 4 0..1 arrays with new values 0..1 introduced in row major order and no element equal to more than two of its immediate leftward or upward or left-upward diagonal neighbors.

%I A208265 #8 Jun 29 2018 08:35:25
%S A208265 8,89,1033,11929,137845,1592731,18403423,212644499,2457026181,
%T A208265 28390000737,328035635669,3790326714043,43795780208895,
%U A208265 506043544208099,5847140236199813,67561476345437377,780647102957445445
%N A208265 Number of n X 4 0..1 arrays with new values 0..1 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 A208265 Column 4 of A208269.
%H A208265 R. H. Hardin, <a href="/A208265/b208265.txt">Table of n, a(n) for n = 1..210</a>
%F A208265 Empirical: a(n) = 10*a(n-1) + 20*a(n-2) - 21*a(n-3) - 30*a(n-4) + 8*a(n-5).
%F A208265 Empirical g.f.: x*(8 + 9*x - 17*x^2 - 13*x^3 + 4*x^4) / (1 - 10*x - 20*x^2 + 21*x^3 + 30*x^4 - 8*x^5). - _Colin Barker_, Jun 29 2018
%e A208265 Some solutions for n=4:
%e A208265 ..0..1..1..1....0..0..0..1....0..1..0..1....0..0..0..1....0..0..1..0
%e A208265 ..1..1..0..0....0..1..1..0....1..1..0..1....1..0..1..0....0..1..1..0
%e A208265 ..0..0..1..1....1..1..0..1....0..1..1..0....1..1..1..1....1..1..0..0
%e A208265 ..1..1..0..0....0..0..1..0....0..0..1..1....1..0..1..0....1..0..0..1
%Y A208265 Cf. A208269.
%K A208265 nonn
%O A208265 1,1
%A A208265 _R. H. Hardin_, Feb 24 2012