Number of 6-bead necklaces labeled with numbers -n..n allowing reversal, with sum zero and first and second differences in -n..n.

A208973

Number of 6-bead necklaces labeled with numbers -n..n allowing reversal, with sum zero and first and second differences in -n..n.

Terms

    a(0) =2a(1) =8a(2) =29a(3) =90a(4) =221a(5) =495a(6) =967a(7) =1801a(8) =3093a(9) =5050a(10) =7921a(11) =11994a(12) =17488a(13) =25008a(14) =34797a(15) =47448a(16) =63641a(17) =83953a(18) =108932a(19) =139984a(20) =177423a(21) =222404a(22) =276434a(23) =340397a(24) =415203a(25) =503475a(26) =605600a(27) =723511a(28) =859793a(29) =1015565

External references