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%I #5 Mar 31 2012 12:36:39
%S 114,1368,15476,178834,2076774,24378976,288237528,3427837106,
%T 40950125796,491063998130,5907663402532,71267752107030,
%U 861806880210532,10443265297671942,126784115884242080,1541722886174306634
%N Number of -6..6 arrays x(0..n+1) of n+2 elements with zero sum and nonzero second differences
%C Column 6 of A200553
%H R. H. Hardin, <a href="/A200551/b200551.txt">Table of n, a(n) for n = 1..113</a>
%e Some solutions for n=3
%e .-4....2....0...-1...-4...-3...-1....4...-2...-2....0....4...-5...-6...-2....2
%e ..3....1....3....3....5....0...-2...-2....0....2....2....3....4....3....3...-4
%e .-1...-1....1...-1...-5....0....6....3....5....4...-1...-4...-3...-4....0....0
%e ..1....0...-5....1...-2...-1...-2....1...-5...-5...-6...-2....0....6....2....6
%e ..1...-2....1...-2....6....4...-1...-6....2....1....5...-1....4....1...-3...-4
%K nonn
%O 1,1
%A _R. H. Hardin_ Nov 19 2011