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A208267 Number of nX6 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 A208267 #7 Jul 22 2025 21:15:52
%S A208267 32,1129,42563,1592731,59655167,2234126207,83670667271,3133560234217,
%T A208267 117355367786585,4395090865370635,164601109918978615,
%U A208267 6164497208894901477,230867373009598884627,8646243499452479433569,323811570588787197424201
%N A208267 Number of nX6 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 A208267 Column 6 of A208269
%H A208267 R. H. Hardin, <a href="/A208267/b208267.txt">Table of n, a(n) for n = 1..210</a>
%F A208267 Empirical: a(n) = 36*a(n-1) +120*a(n-2) -2391*a(n-3) -3905*a(n-4) +50702*a(n-5) +27152*a(n-6) -396016*a(n-7) +154999*a(n-8) +751787*a(n-9) -499260*a(n-10) -410368*a(n-11) +355981*a(n-12) +38077*a(n-13) -70276*a(n-14) +6203*a(n-15) +3386*a(n-16) -622*a(n-17) +28*a(n-18)
%e A208267 Some solutions for n=4
%e A208267 ..0..0..0..1..1..0....0..0..0..0..0..0....0..0..0..1..0..0....0..0..0..1..0..0
%e A208267 ..0..1..1..1..0..1....1..0..1..0..1..0....0..1..1..1..0..1....0..1..1..0..0..1
%e A208267 ..1..0..1..0..1..0....0..0..1..0..1..1....0..0..0..1..0..1....0..1..0..0..1..1
%e A208267 ..1..1..0..0..0..0....0..1..0..0..1..0....1..1..1..0..1..0....0..1..1..0..1..0
%K A208267 nonn
%O A208267 1,1
%A A208267 _R. H. Hardin_ Feb 24 2012