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%I #8 Aug 16 2018 08:59:02
%S 3,34,969,64752,5227536,436214328,36601614264,3073970725512,
%T 258205634457816,21689162608860168,1821888109561493784,
%U 153038579509053600072,12855240375043076417496,1079840187251574876131208
%N Number of n X 3 0..6 arrays with no element equal to another at a city block distance of exactly two, and new values 0..6 introduced in row major order.
%C Column 3 of A222779.
%H R. H. Hardin, <a href="/A222778/b222778.txt">Table of n, a(n) for n = 1..25</a>
%F Empirical: a(n) = 101*a(n-1) - 1470*a(n-2) + 3528*a(n-3) for n>5.
%F Empirical g.f.: x*(3 - 269*x + 1945*x^2 + 6279*x^3 - 7938*x^4) / ((1 - 3*x)*(1 - 14*x)*(1 - 84*x)). - _Colin Barker_, Aug 16 2018
%e Some solutions for n=3:
%e ..0..1..2....0..1..2....0..1..2....0..1..1....0..1..2....0..1..2....0..1..2
%e ..3..4..2....3..3..0....3..3..4....0..2..3....3..1..4....2..1..3....0..3..4
%e ..2..5..0....4..2..0....1..0..4....1..4..0....5..0..4....4..5..3....1..2..4
%Y Cf. A222779.
%K nonn
%O 1,1
%A _R. H. Hardin_, Mar 05 2013