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A207721 Number of 6Xn 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 1 and 1 0 0 vertically.

%I A207721 #7 Jul 22 2025 20:43:18
%S A207721 22,484,5302,66946,820820,10150118,125165018,1545006848,19064074106,
%T A207721 235267721766,2903258039792,35827609743354,442126584439650,
%U A207721 5456029684316684,67329644638468630,830875800786510138
%N A207721 Number of 6Xn 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 1 and 1 0 0 vertically.
%C A207721 Row 6 of A207717
%H A207721 R. H. Hardin, <a href="/A207721/b207721.txt">Table of n, a(n) for n = 1..210</a>
%F A207721 Empirical: a(n) = 8*a(n-1) +63*a(n-2) -85*a(n-3) -424*a(n-4) +387*a(n-5) +724*a(n-6) -695*a(n-7) -148*a(n-8) +185*a(n-9) +13*a(n-10) -14*a(n-11) -a(n-12)
%e A207721 Some solutions for n=4
%e A207721 ..1..0..1..0....1..1..1..1....0..1..1..0....0..1..1..0....0..1..0..0
%e A207721 ..1..1..0..0....1..1..1..1....1..1..0..1....1..1..0..1....0..1..0..1
%e A207721 ..0..1..1..0....0..1..0..1....1..0..1..1....1..0..1..1....0..1..0..0
%e A207721 ..1..1..1..0....1..1..1..0....0..1..1..1....0..1..0..1....0..1..0..1
%e A207721 ..0..1..0..0....1..0..1..1....1..1..0..1....1..0..1..1....0..1..0..1
%e A207721 ..1..0..1..0....1..1..0..0....1..1..1..0....1..1..0..1....0..1..0..1
%K A207721 nonn
%O A207721 1,1
%A A207721 _R. H. Hardin_ Feb 19 2012