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%I #12 Mar 12 2017 22:43:19
%S 1,2,5,50,561,10372,243678,7202490,247156839,9762800723,440697781180,
%T 22158315689027,1229209301535779,75088178610750205,
%U 4978494160384332078,356259456157306682274,27485448424107064539043,2265348987116189301685523,198721340483996173886242478,18537738405130256739553691845
%N Number of n-bead necklaces labeled with numbers -n..n allowing reversal, with sum zero and three times sum of squares <= n^2*(n+1).
%e Some solutions for n=4:
%e .-1...-4...-3...-1...-3...-3...-2...-3...-3...-4...-3...-3...-4...-2...-2...-2
%e .-1....0....1....1....1....2....0....0....0....1...-1...-1....1...-2....0....2
%e .-1....3....1...-1...-1...-2...-2...-1....0....1....0....2....0....0...-1...-2
%e ..3....1....1....1....3....3....4....4....3....2....4....2....3....4....3....2
%Y Diagonal of A208805.
%K nonn
%O 1,2
%A _R. H. Hardin_, Mar 01 2012
%E a(10)-a(20) from _Andrew Howroyd_, Mar 02 2017
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