2-Bell numbers: a(n) = number of partitions of [n+1] with a distinguished block.
A005493
2-Bell numbers: a(n) = number of partitions of [n+1] with a distinguished block.
Terms
- a(0) =1a(1) =3a(2) =10a(3) =37a(4) =151a(5) =674a(6) =3263a(7) =17007a(8) =94828a(9) =562595a(10) =3535027a(11) =23430840a(12) =163254885a(13) =1192059223a(14) =9097183602a(15) =72384727657a(16) =599211936355
External references
- oeis: A005493