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%I #5 Mar 31 2012 12:36:53
%S 128,1576,17296,207184,2537024,31155004,384996502,4786979780,
%T 59791891464,749603860520,9427927830076,118904758131236,
%U 1503198371854568,19043136745799960,241690849746856584,3072505406058890180
%N Number of arrays of n+2 integers in -7..7 with sum zero and adjacent elements differing in absolute value
%C Column 7 of A202962
%H R. H. Hardin, <a href="/A202961/b202961.txt">Table of n, a(n) for n = 1..210</a>
%e Some solutions for n=3
%e ..4...-3....6...-6...-4...-7...-1....1...-3....0....1...-7....0....0....5....1
%e ..2....7....0....0...-6....1...-3....0...-4....7...-7...-1....2...-3....2....3
%e .-5....2...-7....5....0...-5....1....2....2...-6...-1....7....7....1...-4....1
%e ..6....0...-6...-3....4....4....0...-5...-1...-3....2....2...-3....0...-1...-5
%e .-7...-6....7....4....6....7....3....2....6....2....5...-1...-6....2...-2....0
%K nonn
%O 1,1
%A _R. H. Hardin_ Dec 26 2011
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