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%I #5 Mar 31 2012 12:36:44
%S 1,7,57,297,1333,6019,27087,126147,592487,2795067,13283639,63243395,
%T 302028473,1447178413,6955639001,33526007827,161977137395,
%U 784134070729,3802451672491,18466210763809,89797281724981,437189848462945
%N Number of zero-sum -7..7 arrays of n elements with first through fourth differences also in -7..7
%C Column 7 of A201439
%H R. H. Hardin, <a href="/A201438/b201438.txt">Table of n, a(n) for n = 1..52</a>
%e Some solutions for n=7
%e .-6...-2....2...-4...-3....4...-3...-3...-7...-5...-3....1....3....5....0...-3
%e .-6...-3....1....1...-5....0....4...-3...-6....1....3...-6....3...-1...-3...-2
%e .-4...-1....0....6...-3...-2....7...-2...-2....3....3...-6....0...-3...-2...-1
%e .-1....0....0....6....0...-4....4...-2....2....3...-1...-3...-3...-2....0....2
%e ..3....2...-1....1....4...-3...-1....1....4....1...-3....1...-4...-1....4....3
%e ..7....4...-1...-5....5....0...-5....4....6....0...-2....6...-1....1....4....1
%e ..7....0...-1...-5....2....5...-6....5....3...-3....3....7....2....1...-3....0
%K nonn
%O 1,2
%A _R. H. Hardin_ Dec 01 2011
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