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%I #7 Oct 02 2018 06:32:24
%S 11,76,521,3588,24719,170270,1172854,8078859,55648831,383320506,
%T 2640389883,18187544432,125279518221,862950891715,5944181874953,
%U 40944737993493,282035712335780,1942719551542674,13381848790314938
%N Number of (n+1) X (2+1) 0..1 arrays with every element equal to some horizontal, vertical or antidiagonal neighbor, with top left element zero.
%H R. H. Hardin, <a href="/A232032/b232032.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 7*a(n-1) - 5*a(n-3) - 2*a(n-4) - a(n-5) + 2*a(n-6) + 2*a(n-7) for n>8.
%F Empirical g.f.: x*(11 - x - 11*x^2 - 4*x^3 + 5*x^4 + 5*x^5 - x^7) / (1 - 7*x + 5*x^3 + 2*x^4 + x^5 - 2*x^6 - 2*x^7). - _Colin Barker_, Oct 02 2018
%e Some solutions for n=6:
%e ..0..0..0....0..0..0....0..0..0....0..0..0....0..0..1....0..0..0....0..0..1
%e ..1..0..0....1..1..0....0..0..1....0..0..0....0..1..1....0..1..1....0..1..0
%e ..1..1..0....1..1..0....1..1..0....0..1..0....1..0..0....0..0..1....0..0..0
%e ..1..1..1....1..0..1....0..0..1....1..1..1....1..1..0....0..0..0....1..0..1
%e ..1..0..1....1..0..1....0..0..1....0..1..0....1..1..1....0..1..0....1..1..0
%e ..1..0..1....0..0..0....1..1..1....0..0..0....0..0..1....1..1..0....0..0..0
%e ..1..0..1....1..1..1....0..0..1....1..1..1....1..1..1....1..1..0....1..1..0
%Y Column 2 of A232038.
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 17 2013
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