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A209096 Number of n X 4 0..2 arrays with new values 0..2 introduced in row major order and no element equal to more than one of its immediate leftward or upward or right-upward antidiagonal neighbors.

%I A209096 #9 Jul 08 2018 10:48:18
%S A209096 14,520,20928,849548,34538488,1404480904,57113932788,2322577420320,
%T A209096 94449268074144,3840847202693708,156190807044264984,
%U A209096 6351611234890358120,258292828185791666996,10503663185141042925120,427138999879594132134016
%N A209096 Number of n X 4 0..2 arrays with new values 0..2 introduced in row major order and no element equal to more than one of its immediate leftward or upward or right-upward antidiagonal neighbors.
%C A209096 Column 4 of A209100.
%H A209096 R. H. Hardin, <a href="/A209096/b209096.txt">Table of n, a(n) for n = 1..210</a>
%F A209096 Empirical: a(n) = 49*a(n-1) - 356*a(n-2) + 705*a(n-3) - 425*a(n-4) + 64*a(n-5) for n>6.
%F A209096 Empirical g.f.: 2*x*(7 - 83*x + 216*x^2 - 337*x^3 + 177*x^4 - 28*x^5) / (1 - 49*x + 356*x^2 - 705*x^3 + 425*x^4 - 64*x^5). - _Colin Barker_, Jul 08 2018
%e A209096 Some solutions for n=4:
%e A209096 ..0..1..2..1....0..0..0..0....0..0..0..0....0..0..0..1....0..0..0..1
%e A209096 ..2..0..0..0....1..1..1..2....1..1..1..0....2..1..0..2....1..1..2..0
%e A209096 ..0..2..2..0....2..0..1..0....0..2..0..2....2..0..1..2....0..1..2..2
%e A209096 ..0..1..0..1....1..2..0..2....2..0..1..1....1..0..1..2....0..0..0..2
%Y A209096 Cf. A209100.
%K A209096 nonn
%O A209096 1,1
%A A209096 _R. H. Hardin_, Mar 05 2012