A058699 a(n) = p(p(n)), p = partition numbers A000041.

1, 1, 2, 3, 7, 15, 56, 176, 1002, 5604, 53174, 526823, 10619863, 214481126, 9035836076, 476715857290, 51820051838712, 7479565078510584, 2645418340688763701, 1318520401612270233223, 1774758704783877366657989, 4025091510519029370421431033

Offset

0,3

Links

Alois P. Heinz, Table of n, a(n) for n = 0..50

Formula

a(n) = A000041(A000041(n)). - Omar E. Pol, Apr 25 2016

Maple

a:= n-> (combinat[numbpart]@@2)(n):
seq(a(n), n=0..22);  # Alois P. Heinz, Apr 05 2017

Mathematica

Table[Nest[PartitionsP, n, 2], {n, 0, 20}] (* Michael De Vlieger, Apr 25 2016 *)

Prog

(PARI) a(n) = numbpart(numbpart(n)); \\ Michel Marcus, Apr 25 2016

Crossrefs

Cf. A000009, A000041, A284908, A284909, A284910.

Sequence in context: A110888 A133736 A058698 * A250193 A004782 A049956

Adjacent sequences: A058696 A058697 A058698 * A058700 A058701 A058702

Keyword

nonn

Author

N. J. A. Sloane, Dec 31 2000

Status

approved