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%I #9 Dec 31 2018 06:16:01
%S 2,4,8,15,29,57,114,228,456,911,1821,3641,7282,14564,29128,58255,
%T 116509,233017,466034,932068,1864136,3728271,7456541,14913081,
%U 29826162,59652324,119304648,238609295,477218589,954437177,1908874354,3817748708
%N Number of (n+3) X (1+3) 0..1 arrays with each row and column divisible by 9, read as a binary number with top and left being the most significant bits.
%H R. H. Hardin, <a href="/A262333/b262333.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 3*a(n-1) - 2*a(n-2) - a(n-3) + 3*a(n-4) - 2*a(n-5).
%F Empirical g.f.: x*(2 - 2*x + x^3 - 2*x^4) / ((1 - x)*(1 + x)*(1 - 2*x)*(1 - x + x^2)). - _Colin Barker_, Dec 31 2018
%e Some solutions for n=4:
%e ..0..0..0..0....1..0..0..1....0..0..0..0....1..0..0..1....0..0..0..0
%e ..0..0..0..0....1..0..0..1....1..0..0..1....1..0..0..1....1..0..0..1
%e ..0..0..0..0....1..0..0..1....1..0..0..1....1..0..0..1....0..0..0..0
%e ..0..0..0..0....0..0..0..0....1..0..0..1....1..0..0..1....0..0..0..0
%e ..0..0..0..0....1..0..0..1....1..0..0..1....1..0..0..1....1..0..0..1
%e ..0..0..0..0....0..0..0..0....1..0..0..1....1..0..0..1....0..0..0..0
%e ..0..0..0..0....1..0..0..1....1..0..0..1....0..0..0..0....0..0..0..0
%Y Column 1 of A262338.
%K nonn
%O 1,1
%A _R. H. Hardin_, Sep 18 2015
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