Number of different energy states of n positive and n negative charges on a necklace. Different sets of distances between n points chosen from 2n equally spaced points on a circle.
A045611
Number of different energy states of n positive and n negative charges on a necklace. Different sets of distances between n points chosen from 2n equally spaced points on a circle.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =3a(4) =7a(5) =13a(6) =35a(7) =85a(8) =254a(9) =701a(10) =2377a(11) =7944a(12) =25220a(13) =95910a(14) =332300a(15) =1164825a(16) =4379920a(17) =16649851a(18) =58473414
External references
- oeis: A045611