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%I #9 Jun 12 2018 11:12:44
%S 194,1512,13068,113592,992088,8636544,75419136,656729088,5733618048,
%T 49937319936,435896552448,3797147043840,33139377911808,
%U 288724641841152,2519477853880320,21953583883419648,191549577961635840
%N Number of (n+1) X 4 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 3 of A205626.
%H R. H. Hardin, <a href="/A205621/b205621.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 72*a(n-2) + 48*a(n-3) - 112*a(n-4) for n>5.
%F Empirical g.f.: 2*x*(97 + 756*x - 450*x^2 - 2292*x^3 + 172*x^4) / (1 - 72*x^2 - 48*x^3 + 112*x^4). - _Colin Barker_, Jun 12 2018
%e Some solutions for n=4:
%e ..0..0..1..1....0..1..2..0....0..1..1..2....0..1..2..0....0..0..0..0
%e ..0..1..1..0....0..1..2..0....1..1..2..2....2..0..1..2....0..1..0..2
%e ..0..2..2..0....2..0..1..2....2..0..0..0....2..0..1..2....0..1..0..2
%e ..0..0..2..2....1..0..1..2....0..0..1..0....2..2..0..1....2..0..0..0
%e ..2..1..1..0....1..1..1..1....1..2..2..0....0..1..0..1....2..1..1..1
%Y Cf. A205626.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 29 2012