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 A208965 Number of n-bead necklaces labeled with numbers -3..3 allowing reversal, with sum zero and first and second differences in -3..3. 1
 1, 1, 2, 4, 9, 29, 87, 325, 1148, 4168, 15250, 57027, 214739, 820038, 3156251, 12243837, 47772129, 187370511, 738088612, 2919087297, 11585698838, 46133010366, 184243108172, 737834327019, 2962231908667, 11920345964795, 48072060624163, 194251242877839 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS Andrew Howroyd, Table of n, a(n) for n = 1..50 EXAMPLE All solutions for n=5: ..0...-2...-1...-1...-1...-2...-1...-1...-2 ..0...-1...-1....0....0...-2...-1....0...-1 ..0....1....0...-1....0....1....1....0....2 ..0....2....1....1....1....2....0....0....2 ..0....0....1....1....0....1....1....1...-1 CROSSREFS Column 3 of A208970. Sequence in context: A005095 A300491 A229686 * A306505 A243789 A214935 Adjacent sequences:  A208962 A208963 A208964 * A208966 A208967 A208968 KEYWORD nonn AUTHOR R. H. Hardin, Mar 03 2012 EXTENSIONS a(19)-a(28) from Andrew Howroyd, Mar 12 2017 STATUS approved

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Last modified December 16 04:22 EST 2019. Contains 330013 sequences. (Running on oeis4.)