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%I #5 Mar 31 2012 12:36:37
%S 1,10,56,324,1948,11962,74338,466548,2947742,18746754,119701782,
%T 767860824,4938868628,31876070432,206122332340,1336425077996,
%U 8676994345132,56457974059982,367738443114696,2399500033305708
%N Number of -5..5 arrays x(0..n-1) of n elements with zero sum and elements alternately strictly increasing and strictly decreasing
%C Column 5 of A200057
%H R. H. Hardin, <a href="/A200054/b200054.txt">Table of n, a(n) for n = 1..200</a>
%e Some solutions for n=6
%e .-2...-5....3...-4...-5....0...-4....5...-2....4....0....5...-4...-2...-2....0
%e .-3....4...-3...-1....4...-3....4...-4...-5...-3....3...-5....0...-3....2....5
%e ..5...-3....4...-5...-1....4...-4....1....2....3...-4....0...-3....2....0....0
%e .-1....2...-5....4....5...-4....3...-5...-3....0...-1...-3....2....0....4....1
%e ..5....0....3....2...-2....5...-4....4....5....1...-3....2....1....3...-3...-5
%e .-4....2...-2....4...-1...-2....5...-1....3...-5....5....1....4....0...-1...-1
%K nonn
%O 1,2
%A _R. H. Hardin_ Nov 13 2011