The maximal number of partitions of {1..2n} that are invariant under a permutation consisting of n 2-cycles, and which have the same number of nonempty parts.
A002873
The maximal number of partitions of {1..2n} that are invariant under a permutation consisting of n 2-cycles, and which have the same number of nonempty parts.
Terms
- a(0) =1a(1) =1a(2) =3a(3) =10a(4) =53a(5) =265a(6) =1700a(7) =13097a(8) =96796a(9) =829080a(10) =8009815a(11) =75604892a(12) =808861988a(13) =9175286549a(14) =106167118057
External references
- oeis: A002873