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A207596 Number of n X 5 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 0 1 and 1 0 1 vertically. 1

%I

%S 15,225,825,1995,3915,6765,10725,15975,22695,31065,41265,53475,67875,

%T 84645,103965,126015,150975,179025,210345,245115,283515,325725,371925,

%U 422295,477015,536265,600225,669075,742995,822165,906765,996975,1092975

%N Number of n X 5 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 0 1 and 1 0 1 vertically.

%C Column 5 of A207599.

%H R. H. Hardin, <a href="/A207596/b207596.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 30*n^3 + 15*n^2 - 45*n + 15.

%F Conjectures from _Colin Barker_, Jun 25 2018: (Start)

%F G.f.: 15*x*(1 + 11*x + x^2 - x^3) / (1 - x)^4.

%F a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4) for n>4.

%F (End)

%e Some solutions for n=4:

%e ..1..1..0..0..1....0..1..1..0..1....1..0..1..1..0....0..1..1..1..1

%e ..1..0..1..1..0....1..0..1..1..0....1..0..1..1..1....1..0..1..1..1

%e ..0..0..1..1..0....0..0..1..1..0....0..0..1..1..1....0..0..1..1..0

%e ..0..0..1..1..0....0..0..1..1..0....0..0..1..1..0....0..0..1..1..0

%Y Cf. A207599.

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 19 2012

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Last modified October 24 02:02 EDT 2021. Contains 348217 sequences. (Running on oeis4.)