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A207449 Number of n X 4 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 1 and 1 0 1 vertically.

%I A207449 #10 Jun 22 2018 15:10:15
%S A207449 10,100,330,760,1450,2460,3850,5680,8010,10900,14410,18600,23530,
%T A207449 29260,35850,43360,51850,61380,72010,83800,96810,111100,126730,143760,
%U A207449 162250,182260,203850,227080,252010,278700,307210,337600,369930,404260,440650
%N A207449 Number of n X 4 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 1 and 1 0 1 vertically.
%C A207449 Column 4 of A207453.
%H A207449 R. H. Hardin, <a href="/A207449/b207449.txt">Table of n, a(n) for n = 1..210</a>
%F A207449 Empirical: a(n) = 10*n^3 + 10*n^2 - 10*n.
%F A207449 Conjectures from _Colin Barker_, Jun 22 2018: (Start)
%F A207449 G.f.: 10*x*(1 + 6*x - x^2) / (1 - x)^4.
%F A207449 a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4) for n>4.
%F A207449 (End)
%e A207449 Some solutions for n=5:
%e A207449 ..1..0..1..0....1..0..1..0....1..1..1..0....0..1..1..0....1..1..0..0
%e A207449 ..1..0..1..1....1..1..1..1....0..1..1..1....1..1..0..1....1..0..1..0
%e A207449 ..1..0..1..1....0..1..0..1....0..1..0..0....1..1..0..0....1..0..1..0
%e A207449 ..1..0..1..0....0..1..0..0....0..1..0..0....0..1..0..0....1..0..1..0
%e A207449 ..1..0..1..0....0..1..0..0....0..1..0..0....0..1..0..0....1..0..1..0
%Y A207449 Cf. A207453.
%K A207449 nonn
%O A207449 1,1
%A A207449 _R. H. Hardin_, Feb 17 2012