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A232070 Number of (n+1) X (2+1) 0..1 arrays with every element equal to some horizontal, diagonal or antidiagonal neighbor, with top left element zero. 1

%I

%S 15,87,602,3985,26713,178484,1193537,7979619,53352090,356709629,

%T 2384952501,15945724308,106612681357,712809462455,4765824578786,

%U 31864172723641,213042987115297,1424399583243252,9523496644232169

%N Number of (n+1) X (2+1) 0..1 arrays with every element equal to some horizontal, diagonal or antidiagonal neighbor, with top left element zero.

%H R. H. Hardin, <a href="/A232070/b232070.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 5*a(n-1) + 11*a(n-2) + 2*a(n-3) - 8*a(n-5).

%F Empirical g.f.: x*(15 + 12*x + 2*x^2 - 12*x^3 - 8*x^4) / (1 - 5*x - 11*x^2 - 2*x^3 + 8*x^5). - _Colin Barker_, Oct 03 2018

%e Some solutions for n=6:

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

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

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

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

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

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

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

%Y Column 2 of A232076.

%K nonn

%O 1,1

%A _R. H. Hardin_, Nov 17 2013

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Last modified July 24 05:05 EDT 2021. Contains 346273 sequences. (Running on oeis4.)