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%I #9 Jun 12 2018 09:49:34
%S 50,306,2052,13800,92934,625512,4211904,28351440,190894488,1285019424,
%T 8651903808,58242716160,392131883616,2639804254848,17772730684416,
%U 119646649486080,805521704829312,5422860687684096,36509097713452032
%N Number of (n+1) X 3 0..2 arrays with every 2 X 2 subblock in a row having an equal number of equal diagonal or equal antidiagonal elements, adjacent rows differing in this number, and new values 0..2 introduced in row major order.
%C Column 2 of A205626.
%H R. H. Hardin, <a href="/A205620/b205620.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 40*a(n-2) + 40*a(n-3) - 28*a(n-4) for n>5.
%F Empirical g.f.: 2*x*(25 + 153*x + 26*x^2 - 220*x^3 + 7*x^4) / (1 - 40*x^2 - 40*x^3 + 28*x^4). - _Colin Barker_, Jun 12 2018
%e Some solutions for n=4:
%e ..0..0..1....0..0..0....0..0..1....0..0..0....0..0..1....0..0..0....0..0..0
%e ..1..0..0....1..2..1....2..0..0....0..1..0....2..2..1....0..0..0....0..0..0
%e ..2..2..1....2..2..2....1..1..1....1..0..1....0..2..2....0..1..0....0..1..0
%e ..0..2..2....0..0..0....2..1..0....0..2..0....1..1..0....1..0..1....1..0..1
%e ..0..1..1....1..0..1....2..1..2....2..0..2....2..1..1....2..0..2....2..1..2
%Y Cf. A205626.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 29 2012