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%I #5 Mar 31 2012 12:36:37
%S 1,6,22,78,288,1098,4224,16432,64310,253692,1003374,3992358,15908668,
%T 63684848,255153798,1026057576,4127971346,16658240722,67237254862,
%U 272092306164,1101134446908,4466186295698,18113540529096,73607652658268
%N Number of -3..3 arrays x(0..n-1) of n elements with zero sum and elements alternately strictly increasing and strictly decreasing
%C Column 3 of A200057
%H R. H. Hardin, <a href="/A200052/b200052.txt">Table of n, a(n) for n = 1..200</a>
%e Some solutions for n=6
%e .-1...-2....0...-2...-1....1....0...-2...-1....3...-1....1....0....0...-2....1
%e .-3....0....2....1....1...-2....3....3...-3....0...-3...-2...-1....3....2...-1
%e ..3...-1...-3...-2...-2....3...-1....1....2....2....3....3....3...-1....0....1
%e .-1....1....2....2....2...-3....3....3...-1...-3....0...-2....0....1....2...-1
%e ..2...-1...-3....0...-2....1...-3...-3....2....1....3....2....1...-3...-2....1
%e ..0....3....2....1....2....0...-2...-2....1...-3...-2...-2...-3....0....0...-1
%K nonn
%O 1,2
%A _R. H. Hardin_ Nov 13 2011
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