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%I #9 Jun 22 2018 07:08:25
%S 21,441,2307,7561,19319,42167,82477,148743,251937,405885,627663,
%T 938013,1361779,1928363,2672201,3633259,4857549,6397665,8313339,
%U 10672017,13549455,17030335,21208901,26189615,32087833,39030501,47156871,56619237
%N Number of n X 6 0..1 arrays avoiding 0 0 1 and 0 1 0 horizontally and 0 0 1 and 1 1 0 vertically.
%C Column 6 of A207391.
%H R. H. Hardin, <a href="/A207389/b207389.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = (1/36)*n^6 + (113/60)*n^5 + (151/9)*n^4 + (95/4)*n^3 - (605/36)*n^2 - (229/30)*n + 3.
%F Conjectures from _Colin Barker_, Jun 22 2018: (Start)
%F G.f.: x*(21 + 294*x - 339*x^2 - 62*x^3 + 139*x^4 - 36*x^5 + 3*x^6) / (1 - x)^7.
%F a(n) = 7*a(n-1) - 21*a(n-2) + 35*a(n-3) - 35*a(n-4) + 21*a(n-5) - 7*a(n-6) + a(n-7) for n>7.
%F (End)
%e Some solutions for n=4:
%e ..0..0..0..0..0..0....0..0..0..0..0..0....1..1..1..1..1..1....1..1..0..0..0..0
%e ..0..1..1..1..0..1....1..1..1..1..1..0....1..1..1..1..0..1....1..0..1..1..0..1
%e ..0..1..1..0..0..0....1..1..0..1..1..0....1..1..1..1..1..1....1..1..1..1..0..1
%e ..0..1..1..0..0..0....1..1..1..1..1..0....1..1..1..1..0..1....1..1..1..1..0..1
%Y Cf. A207391.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 17 2012
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