A361589 Number of acyclic digraphs on n unlabeled nodes without isolated nodes.

1, 0, 1, 4, 25, 271, 5682, 237684, 20042357, 3404651985, 1162523674892, 796395726736678, 1093229314594543016, 3004753338859186373234, 16527845763725396055765240, 181891586856152393087373330332, 4004313490358484085907684748704180, 176328671349936542115174881107633828418

Offset

0,4

Links

Table of n, a(n) for n=0..17.

Formula

a(n) = A003087(n) - A003087(n-1) for n >= 1.

Prog

(PARI) A361589seq(16) \\ See PARI link in A350794 for program code.

Crossrefs

Row sums of A361588.

Cf. A003087, A350794.

Sequence in context: A376160 A308008 A144281 * A320569 A058791 A216660

Adjacent sequences: A361586 A361587 A361588 * A361590 A361591 A361592

Keyword

nonn

Author

Andrew Howroyd, Mar 16 2023

Status

approved