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A207255 Number of 4 X n 0..1 arrays avoiding 0 0 1 and 1 0 1 horizontally and 0 1 0 and 1 0 1 vertically.

%I A207255 #9 Jun 21 2018 10:31:58
%S A207255 10,100,370,940,1950,3560,5950,9320,13890,19900,27610,37300,49270,
%T A207255 63840,81350,102160,126650,155220,188290,226300,269710,319000,374670,
%U A207255 437240,507250,585260,671850,767620,873190,989200,1116310,1255200,1406570
%N A207255 Number of 4 X n 0..1 arrays avoiding 0 0 1 and 1 0 1 horizontally and 0 1 0 and 1 0 1 vertically.
%C A207255 Row 4 of A207254.
%H A207255 R. H. Hardin, <a href="/A207255/b207255.txt">Table of n, a(n) for n = 1..210</a>
%F A207255 Empirical: a(n) = (5/6)*n^4 + (35/3)*n^3 - (5/6)*n^2 - (5/3)*n.
%F A207255 Conjectures from _Colin Barker_, Jun 21 2018: (Start)
%F A207255 G.f.: 10*x*(1 + 5*x - 3*x^2 - x^3) / (1 - x)^5.
%F A207255 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 A207255 (End)
%e A207255 Some solutions for n=4:
%e A207255 ..0..0..0..0....1..0..0..0....0..1..0..0....1..1..1..1....0..1..0..0
%e A207255 ..0..1..1..0....0..0..0..0....0..1..0..0....1..1..1..1....1..1..1..0
%e A207255 ..0..1..1..0....0..0..0..0....1..0..0..0....1..1..1..1....1..1..1..1
%e A207255 ..1..0..0..0....1..0..0..0....1..0..0..0....1..1..1..1....0..1..1..1
%Y A207255 Cf. A207254.
%K A207255 nonn
%O A207255 1,1
%A A207255 _R. H. Hardin_, Feb 16 2012