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A209478 Number of n-bead necklaces labeled with numbers -1..1 allowing reversal, with sum zero and avoiding the patterns z z+1 z+2 and z z-1 z-2.

%I A209478 #6 Mar 12 2017 23:33:22
%S A209478 1,2,1,4,4,11,15,43,77,199,423,1080,2514,6355,15529,39429,98875,
%T A209478 252551,643133,1653677,4254070,11005241,28518931,74179434,193328017,
%U A209478 505236093,1322919905,3471492272,9125743338
%N A209478 Number of n-bead necklaces labeled with numbers -1..1 allowing reversal, with sum zero and avoiding the patterns z z+1 z+2 and z z-1 z-2.
%C A209478 Column 1 of A209485.
%e A209478 Some solutions for n=10:
%e A209478 .-1...-1...-1...-1...-1...-1...-1...-1...-1...-1...-1...-1...-1...-1...-1...-1
%e A209478 .-1....0...-1...-1...-1....0...-1...-1....0....0....0....0...-1...-1...-1...-1
%e A209478 ..1....0....0....0....1....0....1....1...-1...-1...-1....0...-1....0....0....0
%e A209478 .-1...-1....0....0...-1...-1...-1...-1....1....1....1....1....1....0....0....0
%e A209478 ..0....0....0....1....1....0....0....0...-1...-1....0...-1...-1....1....0....0
%e A209478 ..0....0....0....1...-1....0....0....0....0....1....0....0....1....0....0....0
%e A209478 ..0....0....0...-1....1....1...-1....0....0...-1...-1....0....1....0....1....1
%e A209478 ..0....0....1...-1...-1....0....1....1....1....1....1....1....0...-1...-1....1
%e A209478 ..1....1....0....1....1....0....1....0....0....0....0....0....0....1....1....0
%e A209478 ..1....1....1....1....1....1....1....1....1....1....1....0....1....1....1....0
%K A209478 nonn
%O A209478 1,2
%A A209478 _R. H. Hardin_, Mar 09 2012