A101228 Number of weakly connected acyclic digraphs on n unlabeled nodes.

1, 1, 4, 24, 267, 5647, 237317, 20035307, 3404385285, 1162502511721, 796392234736238, 1093228137893084112, 3004752537725051647790, 16527844667281561960220731, 181891583847006693859132403681, 4004313473818592854334088690859030

Offset

1,3

Comments

The multiset transformation gives the number acyclic digraphs on n unlabeled nodes with k components:

1 ;

1 , 1 ;

4 , 1 , 1 ;

24 , 5 , 1 , 1 ;

267 , 28 , 5 , 1 , 1 ;

5647 , 301 , 29 , 5 , 1 , 1 ;

237317 , 6010 , 305 , 29 , 5 , 1 , 1 ; R. J. Mathar, Mar 21 2019

Links

Andrew Howroyd, Table of n, a(n) for n = 1..50

Crossrefs

Row sums of A350449.

Column sums of A350450.

Cf. A003087 (Euler trans.), A082402, A350451.

Sequence in context: A192983 A077700 A080489 * A009104 A255440 A052727

Adjacent sequences: A101225 A101226 A101227 * A101229 A101230 A101231

Keyword

nonn

Author

Vladeta Jovovic, Jan 22 2005

Status

approved