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%I #10 Aug 05 2018 08:21:35
%S 0,5,39,292,2088,14799,104532,737498,5200799,36668393,258507703,
%T 1822366939,12846614967,90560097250,638385027225,4500153384191,
%U 31722787454665,223622276075576,1576371711149454,11112253094012636
%N Number of n X 2 arrays of occupancy after each element moves to some horizontal, vertical or antidiagonal neighbor, with no 2-loops and with no occupancy greater than 2.
%C Column 2 of A221361.
%H R. H. Hardin, <a href="/A221357/b221357.txt">Table of n, a(n) for n = 1..192</a>
%F Empirical: a(n) = 12*a(n-1) - 38*a(n-2) + 14*a(n-3) + 59*a(n-4) - 21*a(n-5) - 33*a(n-6) + 16*a(n-7).
%F Empirical g.f.: x^2*(5 - 21*x + 14*x^2 - 4*x^3 - 2*x^4 + 4*x^5) / (1 - 12*x + 38*x^2 - 14*x^3 - 59*x^4 + 21*x^5 + 33*x^6 - 16*x^7). - _Colin Barker_, Aug 05 2018
%e Some solutions for n=3:
%e ..1..2....1..1....0..2....1..2....1..1....0..1....0..2....1..0....1..1....1..1
%e ..1..1....1..2....1..1....1..1....2..2....1..1....1..2....2..1....1..1....2..1
%e ..0..1....0..1....1..1....1..0....0..0....2..1....0..1....2..0....1..1....1..0
%Y Cf. A221361.
%K nonn
%O 1,2
%A _R. H. Hardin_, Jan 12 2013
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