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%I #8 Jun 06 2018 15:08:31
%S 29731,1883,1990,1914,2168,2860,3664,6784,15304,36408,95912,258472,
%T 698248,1903432,5196040,14182920,38742920,105842056,289142920,
%U 789944968,2158161544,5896163976,16108606088,44009516680,120236152456,328491253384
%N Number of (n+2) X 9 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 7 of A204284.
%H R. H. Hardin, <a href="/A204283/b204283.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*(29731 - 87310*x - 3659*x^2 - 4056*x^3 + 174812*x^4 + 7654*x^5 - 111900*x^6 - 256*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..1..0..2..1..2..2..1..1....0..0..0..0..0..0..0..0..0
%e ..0..1..0..2..1..2..2..1..1....0..0..0..0..0..0..0..0..0
%e ..0..1..0..2..1..2..2..1..1....1..1..1..1..1..1..1..1..1
%e ..0..1..0..2..1..2..2..1..1....1..1..1..1..1..1..1..1..1
%e ..0..1..0..2..1..2..2..1..1....2..2..2..2..2..2..2..2..2
%e ..0..1..0..2..1..2..2..1..1....1..1..1..1..1..1..1..1..1
%Y Cf. A204284.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 13 2012
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