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%I #8 Aug 15 2018 12:37:46
%S 3,31,306,3014,29671,292017,2873693,28278630,278273755,2738325414,
%T 26946205188,265161285275,2609291560659,25676457366269,
%U 252666460567318,2486337558528381,24466541550530492,240760412205806134
%N Number of 2 X n arrays of occupancy after each element stays put or moves to some horizontal, vertical or antidiagonal neighbor, without move-in move-out left turns.
%C Row 2 of A222093.
%H R. H. Hardin, <a href="/A222094/b222094.txt">Table of n, a(n) for n = 1..170</a>
%F Empirical: a(n) = 17*a(n-1) - 90*a(n-2) + 217*a(n-3) - 258*a(n-4) + 156*a(n-5) - 44*a(n-6) + 4*a(n-7).
%F Empirical g.f.: x*(3 - 20*x + 49*x^2 - 49*x^3 + 20*x^4 - 2*x^5) / (1 - 17*x + 90*x^2 - 217*x^3 + 258*x^4 - 156*x^5 + 44*x^6 - 4*x^7). - _Colin Barker_, Aug 15 2018
%e Some solutions for n=3:
%e ..0..3..0....0..0..1....2..1..0....1..0..2....2..0..0....1..1..1....0..2..0
%e ..0..3..0....3..0..2....1..1..1....3..0..0....0..4..0....2..1..0....3..1..0
%Y Cf. A222093.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 07 2013
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