A338867 Related to the number of Hopf subalgebras of heap-preordered forests of vertex degree n.

1, 1, 5, 38, 424, 6284

Offset

0,3

Comments

It would be nice to have a more precise definition.

Links

Table of n, a(n) for n=0..5.

A. Mansuy, Preordered forests, packed words and contraction algebras, J. Algebra 411 (2014) 259-311, Section 3.1.

Crossrefs

Sequence in context: A069471 A355788 A216858 * A110467 A379861 A221845

Adjacent sequences: A338864 A338865 A338866 * A338868 A338869 A338870

Keyword

nonn,more

Author

R. J. Mathar, Nov 13 2020

Status

approved