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%I #4 Mar 31 2012 12:35:55
%S 1,1,15,57,1033,6259,80851,844829,10894795,130817901,1781556515,
%T 23640849007,329173058411,4518115025537,63025886167079
%N Number of strings of n numbers x(i) in -7..7 with sums of x(i) and of x(i)*x(i+1) both zero
%C Column 7 of A183944
%e Some solutions for n=4
%e .-3....0....1...-7....0....2...-4....1...-6...-4....1....0....4....6....0....3
%e .-6...-1....0....0...-2....0....0....0....0....1....2...-4...-1....0....6....0
%e ..6....0....0....0....0....0....4...-1....6....2...-2....0...-2....0....0....0
%e ..3....1...-1....7....2...-2....0....0....0....1...-1....4...-1...-6...-6...-3
%K nonn
%O 1,3
%A _R. H. Hardin_ Jan 08 2011
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