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%I #9 Jun 06 2018 15:09:26
%S 783,865,128,256,334,778,1990,4758,12782,34702,93502,255070,696478,
%T 1900254,5190878,14181022,38738206,105833374,289140766,789937182,
%U 2158145822,5896161310,16108592158,44009486878,120236148766,328491227166
%N Number of (n+2) X 5 0..2 arrays with every 3 X 3 subblock having three equal elements in a row horizontally, vertically, diagonally or antidiagonally exactly three ways, and new values 0..2 introduced in row major order.
%C Column 3 of A204284.
%H R. H. Hardin, <a href="/A204279/b204279.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 3*a(n-1) -6*a(n-4) +4*a(n-6) for n>8.
%F Empirical g.f.: x*(783 - 1484*x - 2467*x^2 - 128*x^3 + 4264*x^4 + 4966*x^5 - 2708*x^6 - 3136*x^7) / ((1 - x)*(1 - 2*x - 2*x^2)*(1 - 2*x^3)). - _Colin Barker_, Jun 06 2018
%e Some solutions for n=4:
%e ..0..0..0..0..0....0..1..0..2..1....0..1..0..2..2....0..0..0..0..0
%e ..1..1..1..1..1....0..1..0..2..1....0..1..0..2..2....0..0..0..0..0
%e ..0..0..0..0..0....0..1..0..2..1....0..1..0..2..2....1..1..1..1..1
%e ..0..0..0..0..0....0..1..0..2..1....0..1..0..2..2....2..2..2..2..2
%e ..1..1..1..1..1....0..1..0..2..1....0..1..0..2..2....0..0..0..0..0
%e ..0..0..0..0..0....0..1..0..2..1....0..1..0..2..2....0..0..0..0..0
%Y Cf. A204284.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 13 2012
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