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%I
%S 105,435,1817,7587,31677,132263,552247,2305835,9627715,40199277,
%T 167846875,700822891,2926195229,12217949255,51014464969,213004292437,
%U 889371840403,3713456951747,15505058633553,64739364520389
%N Number of 0..4 arrays x(0..n+1) of n+2 elements without any two consecutive increases or two consecutive decreases.
%C Column 4 of A200838.
%H R. H. Hardin, <a href="/A200834/b200834.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 5*a(n-1) -4*a(n-2) +3*a(n-3) -3*a(n-4) +a(n-5) -a(n-6).
%F Empirical g.f.: x*(105 - 90*x + 62*x^2 - 73*x^3 + 20*x^4 - 25*x^5) / ((1 - x)*(1 - 4*x - 3*x^3 - x^5)). - _Colin Barker_, Oct 14 2017
%e Some solutions for n=3
%e ..2....4....1....2....3....1....1....1....0....2....4....2....0....1....1....3
%e ..2....3....4....0....0....4....0....2....4....2....4....4....4....1....4....1
%e ..2....3....4....0....2....3....1....2....3....2....1....4....3....3....3....1
%e ..3....4....0....4....1....4....0....1....4....2....3....1....4....2....3....1
%e ..3....3....1....0....2....2....0....2....3....0....1....2....2....4....4....0
%K nonn
%O 1,1
%A _R. H. Hardin_ Nov 23 2011
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