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%I #9 Jul 23 2018 08:43:42
%S 3,9,22,46,86,153,274,511,993,1966,3880,7558,14544,27819,53226,102217,
%T 197056,380656,735334,1418931,2734793,5267460,10145106,19545576,
%U 37670258,72617646,139990248,269844980,520094648,1002351809,1931757285,3723025114
%N Number of n element 0..2 arrays with each element the minimum of 4 adjacent elements of a random 0..2 array of n+3 elements.
%C Column 4 of A217883.
%H R. H. Hardin, <a href="/A217879/b217879.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) + 3*a(n-5) - a(n-6) + a(n-7) + a(n-8) + a(n-9).
%F Empirical g.f.: x*(1 + x^2 + x^3 + x^4)*(3 + x^2 + x^3 + x^4) / (1 - 3*x + 3*x^2 - x^3 - 3*x^5 + x^6 - x^7 - x^8 - x^9). - _Colin Barker_, Jul 23 2018
%e Some solutions for n=4:
%e ..2....0....1....1....2....0....1....1....1....1....1....2....1....0....0....2
%e ..2....0....1....2....2....1....1....2....1....1....1....1....2....2....1....2
%e ..1....1....2....1....0....2....2....0....1....0....2....0....2....2....1....2
%e ..0....1....1....0....0....2....2....0....2....0....0....0....2....0....2....2
%Y Cf. A217883.
%K nonn
%O 1,1
%A _R. H. Hardin_, Oct 14 2012
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