Number of n-bead necklaces labeled with numbers -2..2 not allowing reversal, with sum zero and three times sum of squares <= n*(2)*(2+1).
A208808
Number of n-bead necklaces labeled with numbers -2..2 not allowing reversal, with sum zero and three times sum of squares <= n*(2)*(2+1).
Terms
- a(0) =1a(1) =2a(2) =5a(3) =15a(4) =59a(5) =187a(6) =753a(7) =3125a(8) =12503a(9) =54977a(10) =229533a(11) =1010861a(12) =4476937a(13) =19717931a(14) =89279611a(15) =400928643a(16) =1825710727a(17) =8356818535a(18) =38284519557a(19) =177041554325
External references
- oeis: A208808