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%I #8 Dec 17 2018 09:12:40
%S 22,133,464,1205,2606,4977,8688,14169,21910,32461,46432,64493,87374,
%T 115865,150816,193137,243798,303829,374320,456421,551342,660353,
%U 784784,926025,1085526,1264797,1465408,1688989,1937230,2211881,2514752,2847713
%N Number of length 1+4 0..n arrays with every five consecutive terms having the maximum of some two terms equal to the minimum of the remaining three terms.
%H R. H. Hardin, <a href="/A254699/b254699.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = (5/2)*n^4 + (20/3)*n^3 + (15/2)*n^2 + (13/3)*n + 1.
%F Conjectures from _Colin Barker_, Dec 17 2018: (Start)
%F G.f.: x*(22 + 23*x + 19*x^2 - 5*x^3 + x^4) / (1 - x)^5.
%F a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 5*a(n-4) + a(n-5) for n>5.
%F (End)
%e Some solutions for n=10:
%e ..4....6....1....5...10....4....6....6....2....0....3....2....0....2....8....9
%e ..9....9....1....9....6....4....9....7....0....9....3....7...10...10....9....4
%e ..5....6....1....0....4....3....5....6....2...10....3....1....4....8....9....9
%e ..4....0....4....5...10....2....5....0....9....9....2....2....6....5....8....0
%e ..2...10....3....8....6....3....3....9....7....9....3....4....4....5....6....4
%Y Row 1 of A254698.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 05 2015
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