Number of set partitions of {1, ..., n} with no block containing three distinct cyclically successive vertices.
A323949
Number of set partitions of {1, ..., n} with no block containing three distinct cyclically successive vertices.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =4a(4) =10a(5) =36a(6) =145a(7) =631a(8) =3015a(9) =15563a(10) =86144a(11) =508311a(12) =3180930a(13) =21018999a(14) =146111543a(15) =1065040886a(16) =8117566366a(17) =64531949885a(18) =533880211566
External references
- oeis: A323949