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%I #4 Mar 31 2012 12:35:56
%S 1,31,207,1531,21411,251231,2880959,33207359
%N Number of strings of n+2 numbers x(i) in -6..6 with the sum of x(i) equal to zero and the sums of x(i)*x(i+1) and x(i)*x(i+2) equal to each other
%C Column 6 of A184061
%e Some solutions for n=4
%e .-2...-1...-3...-5....5...-2....1....5....5....0...-2...-4....4....0....2....4
%e ..0....0...-2...-5....5....2...-2....2...-2....0...-4....3...-3....5....0...-6
%e ..0....0....4....5...-5...-5....0....6...-2....4....4....2...-2....2....0....4
%e ..2....1....0....0....0....0...-2...-4...-2....0....2....2...-1...-5....0....4
%e ..4....2....2....5...-5....6...-1...-3....2....0...-4....2....3....1...-2...-2
%e .-4...-2...-1....0....0...-1....4...-6...-1...-4....4...-5...-1...-3....0...-4
%K nonn
%O 1,2
%A _R. H. Hardin_ Jan 09 2011