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A209648 Number of n X 6 0..1 arrays avoiding 0 0 1 and 1 0 0 horizontally and 0 0 1 and 1 0 1 vertically.

%I A209648 #8 Jul 12 2018 08:55:48
%S A209648 22,484,2354,7128,16830,34012,61754,103664,163878,247060,358402,
%T A209648 503624,688974,921228,1207690,1556192,1975094,2473284,3060178,3745720,
%U A209648 4540382,5455164,6501594,7691728,9038150,10553972,12252834,14148904,16256878
%N A209648 Number of n X 6 0..1 arrays avoiding 0 0 1 and 1 0 0 horizontally and 0 0 1 and 1 0 1 vertically.
%C A209648 Column 6 of A209650.
%H A209648 R. H. Hardin, <a href="/A209648/b209648.txt">Table of n, a(n) for n = 1..210</a>
%F A209648 Empirical: a(n) = 22*n^4 + (88/3)*n^3 - 22*n^2 - (22/3)*n.
%F A209648 Conjectures from _Colin Barker_, Jul 12 2018: (Start)
%F A209648 G.f.: 22*x*(1 + 17*x + 7*x^2 - x^3) / (1 - x)^5.
%F A209648 a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 5*a(n-4) + a(n-5) for n>5.
%F A209648 (End)
%e A209648 Some solutions for n=4:
%e A209648 ..0..1..0..1..1..0....0..1..0..1..1..0....1..1..1..0..1..0....1..0..1..1..1..0
%e A209648 ..1..0..1..0..1..1....0..0..0..0..0..0....0..0..0..0..0..0....1..1..0..1..1..1
%e A209648 ..0..0..0..0..0..0....0..0..0..0..0..0....0..0..0..0..0..0....1..1..0..1..0..1
%e A209648 ..0..0..0..0..0..0....0..0..0..0..0..0....0..0..0..0..0..0....1..1..0..1..0..1
%Y A209648 Cf. A209650.
%K A209648 nonn
%O A209648 1,1
%A A209648 _R. H. Hardin_, Mar 11 2012