Number of pairings on a bracelet; number of chord diagrams that can be turned over and having n chords.
A054499
Number of pairings on a bracelet; number of chord diagrams that can be turned over and having n chords.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =5a(4) =17a(5) =79a(6) =554a(7) =5283a(8) =65346a(9) =966156a(10) =16411700a(11) =312700297a(12) =6589356711a(13) =152041845075
External references
- oeis: A054499