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%I #7 Mar 31 2012 12:36:10
%S 0,6,18,80,296,1154,4376,16547,62222,233880,878268,3297368,12383528,
%T 46541138,175070668,659220634,2485025556,9378589340,35437315784,
%U 134061346668,507765754320,1925456658954,7309793143626,27782162090527
%N Number of strictly increasing arrangements of n nonzero numbers in -(n+4)..(n+4) with sum zero
%C Column 6 of A188122
%H R. H. Hardin, <a href="/A188119/b188119.txt">Table of n, a(n) for n = 1..27</a>
%e Some solutions for n=7
%e .-9..-11..-11...-7..-11..-11...-7..-10..-11...-9..-11...-9...-8..-10...-9..-11
%e .-4...-6...-3...-4...-7..-10...-6...-9...-8...-5...-7...-6...-7...-9...-8...-7
%e .-1...-5...-2...-3...-6...-6...-1...-8...-4...-3...-6...-5...-5...-6...-4...-1
%e ..1...-1...-1...-2....2....4....2...-2...-3....1...-2...-1...-3....1....2....1
%e ..3....5....1...-1....3....6....3....8....5....2....6....1....6....5....4....3
%e ..4....8....5....6....8....7....4...10...10....6....9....9....7....8....7....7
%e ..6...10...11...11...11...10....5...11...11....8...11...11...10...11....8....8
%K nonn
%O 1,2
%A _R. H. Hardin_ Mar 21 2011
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