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%I #5 Mar 31 2012 12:36:39
%S 1540,19530,221984,2567334,32233938,410475622,5230842688,66651385442,
%T 852399648492,10942076565344,140893244263052,1818559742718468,
%U 23521609925458628,304795848113641082,3956133736667718388
%N Number of -7..7 arrays x(0..n+2) of n+3 elements with zero sum and no two or three adjacent elements summing to zero
%C Column 7 of A200430
%H R. H. Hardin, <a href="/A200429/b200429.txt">Table of n, a(n) for n = 1..74</a>
%e Some solutions for n=3
%e ..4....0....4...-7...-2...-4...-2....0...-2....4....4....4...-4...-4...-7....0
%e .-2...-7....7....2....0....1....1....2...-4...-6...-2...-3....7...-4...-6....5
%e .-4....5...-1....0....7....1....0....1...-2....5....3...-6....1....1....2....6
%e ..5....0...-3...-1....0....7...-7....7....3...-7...-4....1....0....1....6....1
%e .-3....4...-2....6...-5....0....6...-4....6...-3...-4....6...-3....7....7...-5
%e ..0...-2...-5....0....0...-5....2...-6...-1....7....3...-2...-1...-1...-2...-7
%K nonn
%O 1,1
%A _R. H. Hardin_ Nov 17 2011
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