Number of 4-bead necklaces labeled with numbers -n..n not allowing reversal, with sum zero and first and second differences in -n..n.
A209008
Number of 4-bead necklaces labeled with numbers -n..n not allowing reversal, with sum zero and first and second differences in -n..n.
Terms
- a(0) =1a(1) =3a(2) =5a(3) =10a(4) =16a(5) =26a(6) =38a(7) =55a(8) =75a(9) =101a(10) =131a(11) =168a(12) =210a(13) =260a(14) =316a(15) =381a(16) =453a(17) =535a(18) =625a(19) =726a(20) =836a(21) =958a(22) =1090a(23) =1235a(24) =1391a(25) =1561a(26) =1743a(27) =1940a(28) =2150a(29) =2376
External references
- oeis: A209008