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%I #8 Oct 06 2018 03:53:11
%S 4,16,216,710,3648,25642,139456,683250,3950740,22616130,120525288,
%T 658213410,3693117580,20305930298,110933224304,613037501594,
%U 3386085231380,18604669612418,102411236923656,564815468453874
%N Number of (1+1) X (n+1) 0..2 arrays with every element next to itself plus and minus one within the range 0..2 horizontally, diagonally or antidiagonally.
%H R. H. Hardin, <a href="/A232840/b232840.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 2*a(n-1) + 3*a(n-2) + 66*a(n-3) + 150*a(n-4) - 86*a(n-5) - 36*a(n-6) - 176*a(n-7) - 512*a(n-8).
%F Empirical g.f.: 2*x*(2 + 4*x + 86*x^2 - 17*x^3 - 38*x^4 - 48*x^5 - 256*x^6) / (1 - 2*x - 3*x^2 - 66*x^3 - 150*x^4 + 86*x^5 + 36*x^6 + 176*x^7 + 512*x^8). - _Colin Barker_, Oct 06 2018
%e Some solutions for n=5:
%e ..1..0..0..2..1..0....0..1..0..0..1..2....0..2..2..0..1..0....0..1..0..2..2..0
%e ..1..2..0..1..2..0....0..1..2..1..2..0....2..1..1..1..0..2....2..1..2..1..1..0
%Y Row 1 of A232839.
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 30 2013
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