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A208266 Number of nX5 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 A208266 #7 Jul 22 2025 21:15:46
%S A208266 16,317,6631,137845,2867739,59655167,1240971177,25815151595,
%T A208266 537016650729,11171225344081,232388094425359,4834225856311743,
%U A208266 100563411775559793,2091958482792842737,43517718984137019457,905272203611654999429
%N A208266 Number of nX5 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 A208266 Column 5 of A208269
%H A208266 R. H. Hardin, <a href="/A208266/b208266.txt">Table of n, a(n) for n = 1..210</a>
%F A208266 Empirical: a(n) = 21*a(n-1) +9*a(n-2) -278*a(n-3) +73*a(n-4) +790*a(n-5) -662*a(n-6) +29*a(n-7) +69*a(n-8) -10*a(n-9)
%e A208266 Some solutions for n=4
%e A208266 ..0..0..1..0..0....0..1..1..0..0....0..0..0..0..0....0..1..1..1..1
%e A208266 ..1..1..1..1..0....0..1..0..0..1....1..1..0..1..0....1..0..0..0..0
%e A208266 ..1..0..1..0..0....1..0..0..1..1....1..0..1..1..1....1..1..1..1..0
%e A208266 ..1..1..1..0..1....0..1..1..0..0....1..1..1..0..1....0..1..0..0..1
%K A208266 nonn
%O A208266 1,1
%A A208266 _R. H. Hardin_ Feb 24 2012