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%I #4 Apr 18 2012 05:40:44
%S 68,516,3848,28464,208560,1516160,10941536,78444752,559061552,
%T 3962850688,27952463280,196285510848,1372724453104,9564449019232,
%U 66413636701040,459728500804384,3173268698181920,21846285064971776,150040513219495120
%N Number of -4..4 arrays x(i) of n+1 elements i=1..n+1 with x(i)+x(j), x(i+1)+x(j+1), -(x(i)+x(j+1)), and -(x(i+1)+x(j)) having three or four distinct values for every i<=n and j<=n
%H R. H. Hardin, <a href="/A211691/b211691.txt">Table of n, a(n) for n = 1..210</a>
%e Some solutions for n=5
%e .-4...-1...-3...-1...-3...-2...-4...-4...-4...-2...-1...-3...-4....0....0...-4
%e .-2....2...-4....4....3...-1....1....2....1...-4...-2...-1....0...-3...-4....2
%e ..0....3....1...-2....1...-3....0...-3...-2....1...-1....0....2....3...-1....4
%e ..4....4....3....0...-4....0...-4....4....0....0...-4....4...-3...-3....4...-4
%e ..3....1....0...-1....3...-1....0...-2...-3...-4....4...-3...-2....3....1....2
%e .-4....2....3....4....1....1....2....0....0....1....2....3...-3...-2....0....0
%K nonn
%O 1,1
%A _R. H. Hardin_ Apr 18 2012
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