The number of partitions of {1..3n} that are invariant under a permutation consisting of n 3-cycles.
A002874
The number of partitions of {1..3n} that are invariant under a permutation consisting of n 3-cycles.
Terms
- a(0) =1a(1) =2a(2) =8a(3) =42a(4) =268a(5) =1994a(6) =16852a(7) =158778a(8) =1644732a(9) =18532810a(10) =225256740a(11) =2933174842a(12) =40687193548a(13) =598352302474
External references
- oeis: A002874