A289680 a(n) = Catalan(n+1)*Bell(n).

1, 2, 10, 70, 630, 6864, 87087, 1254110, 20128680, 355185012, 6817706350, 141150702840, 3130281211300, 73933388090280, 1850739337395090, 48898191857790150, 1358695827817964130, 39579468688851814800, 1205409232277565987210, 38286822212810480963940, 1265497066771343361031440

Offset

0,2

Links

Michael De Vlieger, Table of n, a(n) for n = 0..446

Paul Tarau, A Hiking Trip Through the Orders of Magnitude: Deriving Efficient Generators for Closed Simply-Typed Lambda Terms and Normal Forms, arXiv preprint arXiv:1608.03912 [cs.PL], 2016. See Example 5.

Mathematica

Array[CatalanNumber[# + 1] BellB[#] &, 21, 0] (* Michael De Vlieger, Aug 04 2017 *)

Crossrefs

Cf. A000108, A000110, A064299, A289679.

Sequence in context: A036075 A212914 A123881 * A089845 A293962 A104602

Adjacent sequences: A289677 A289678 A289679 * A289681 A289682 A289683

Keyword

nonn

Author

N. J. A. Sloane, Aug 04 2017

Status

approved