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A208802 Number of n-bead necklaces labeled with numbers -5..5 allowing reversal, with sum zero and three times sum of squares <= n*(5)*(5+1). 1

%I #11 Mar 12 2017 22:49:19

%S 1,4,12,84,561,4566,38668,347219,3174337,29584366,281335070,

%T 2698884632,26233302819,257404858844,2542798716528,25321003256022,

%U 253598478348859,2553267620742628,25839412648600258,262578227718642301

%N Number of n-bead necklaces labeled with numbers -5..5 allowing reversal, with sum zero and three times sum of squares <= n*(5)*(5+1).

%H Andrew Howroyd, <a href="/A208802/b208802.txt">Table of n, a(n) for n = 1..50</a>

%e Some solutions for n=6:

%e .-3...-4...-3...-4...-4...-4...-4...-3...-4...-3...-3...-3...-5...-3...-5...-5

%e ..0...-2...-1....1...-3...-1...-1....0...-1...-1...-1...-1...-2...-1...-1...-2

%e .-3....3....1...-2....1....3...-1...-1....2....5....2....3....0....5....2....1

%e ..1....4...-1....3....2...-3....5....0...-2....1....4....0....4...-2...-1...-1

%e ..1...-2....1....1...-1....2....0....4....3...-2...-2...-2....0...-1....1....3

%e ..4....1....3....1....5....3....1....0....2....0....0....3....3....2....4....4

%Y Column 5 of A208805.

%K nonn

%O 1,2

%A _R. H. Hardin_, Mar 01 2012

%E a(13)-a(20) from _Andrew Howroyd_, Mar 02 2017

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Last modified April 24 22:17 EDT 2024. Contains 371964 sequences. (Running on oeis4.)