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Number of (n+1) X (4+1) 0..1 arrays with each row divisible by 3 and column not divisible by 3, read as a binary number with top and left being the most significant bits.
1

%I #8 Dec 31 2018 11:25:04

%S 0,114,1260,18228,200880,2353338,25901100,289462380,3184570800,

%T 35172555474,386913644460,4260476333988,46865727906480,

%U 515660423584938,5672279881478700,62399341247906460,686393226739623600

%N Number of (n+1) X (4+1) 0..1 arrays with each row divisible by 3 and column not divisible by 3, read as a binary number with top and left being the most significant bits.

%H R. H. Hardin, <a href="/A262416/b262416.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 11*a(n-1) + 48*a(n-2) - 528*a(n-3) - 579*a(n-4) + 6369*a(n-5) + 1612*a(n-6) - 17732*a(n-7).

%F Empirical g.f.: 6*x^2*(19 + x - 184*x^2 + 14*x^3) / ((1 - 2*x)*(1 + 2*x)*(1 - 11*x)*(1 - 13*x^2)*(1 - 31*x^2)). - _Colin Barker_, Dec 31 2018

%e Some solutions for n=4:

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

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

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

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

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

%Y Column 4 of A262420.

%K nonn

%O 1,2

%A _R. H. Hardin_, Sep 22 2015