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%I #5 Mar 31 2012 12:36:11
%S 0,4,12,61,288,1488,7836,42593,236130,1333130,7636298,44294040,
%T 259682196,1536666930,9167492664,55086510571,333133752902,
%U 2026193778596,12387543671686,76088580071361,469354099705916,2906492292139022
%N Number of nondecreasing arrangements of n nonzero numbers in -(n+2)..(n+2) with sum zero
%C Column 4 of A188333
%H R. H. Hardin, <a href="/A188328/b188328.txt">Table of n, a(n) for n = 1..29</a>
%e Some solutions for n=6
%e .-8...-8...-8...-6...-5...-7...-4...-7...-5...-7...-8...-5...-4...-3...-5...-6
%e .-8...-5...-7...-4...-4...-7...-3...-5...-5...-4...-6...-2...-4...-2...-5...-6
%e .-2...-5...-1...-4...-4....1...-1...-5...-4...-3...-2....1...-3...-2...-5...-4
%e ..3....5....4....2...-1....1...-1....4....1....4....3....1....1...-2....4....4
%e ..7....5....4....4....7....5....1....6....5....4....5....1....5....4....4....4
%e ..8....8....8....8....7....7....8....7....8....6....8....4....5....5....7....8
%K nonn
%O 1,2
%A _R. H. Hardin_ Mar 28 2011