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%I
%S 1,5,21,95,443,2191,11107,57203,296293,1541117,8043485,42109417,
%T 221085605,1163918489,6142786425,32491880113,172201763497,
%U 914222792849,4861068133699,25882407886253,137978446814067,736378930368467
%N Number of zero-sum -4..4 arrays of n elements with first and second differences also in -4..4
%C Column 4 of A201873
%H R. H. Hardin, <a href="/A201869/b201869.txt">Table of n, a(n) for n = 1..210</a>
%e Some solutions for n=8
%e .-4....4....1...-2....1....0...-2....3....4....3....1....1....3....2....3....0
%e .-1....0....1....1....0....3...-2....3....0....3....2...-1....2...-2....1...-1
%e ..1....0....2....2...-2....3...-2...-1....0....1....2...-2....3...-4....0...-1
%e ..1...-2....3...-1...-2...-1....1...-1....3...-2...-1....1....1...-4...-2...-1
%e ..0...-1....0...-1....1...-2....2...-3....2...-3...-2....2....0....0...-2....1
%e ..1....0...-3....2....3....0....0...-3...-2...-1....0....1...-2....0....1....0
%e ..1....0...-3....1....1...-1....2....0...-3...-1...-2....0...-3....4....0....1
%e ..1...-1...-1...-2...-2...-2....1....2...-4....0....0...-2...-4....4...-1....1
%K nonn
%O 1,2
%A _R. H. Hardin_ Dec 06 2011
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