Number of n-bead necklaces labeled with numbers -2..2 allowing reversal, with sum zero and three times sum of squares <= n*(2)*(2+1).
A208799
Number of n-bead necklaces labeled with numbers -2..2 allowing reversal, with sum zero and three times sum of squares <= n*(2)*(2+1).
Terms
- a(0) =1a(1) =2a(2) =4a(3) =11a(4) =33a(5) =105a(6) =395a(7) =1612a(8) =6323a(9) =27727a(10) =115117a(11) =506417a(12) =2240045a(13) =9863620a(14) =44646673a(15) =200485659a(16) =912889175a(17) =4178508224a(18) =19142413757a(19) =88521250696a(20) =409486689399
External references
- oeis: A208799