OFFSET
1,6
COMMENTS
Also the number of bipartite (unlabeled) dissections of a polygon.
LINKS
M. Bordirsky, É. Fusy, M. Kang and S. Vigerske, Enumeration of Unlabeled Outerplanar Graphs, 2005
S. Vigerske, Asymptotic enumeration of unlabeled outerplanar graphs, Diploma thesis, Humboldt University Berlin, 2005
S. Vigerske, Homepage
FORMULA
Generating function and cycle index sum known, see Vigerske.
PROG
(PARI) \\ See A295419 for DissectionsModDihedral.
{my(N=50); DissectionsModDihedral(vector(N, n, n%2==0)) + vector(N, n, n==2)} \\ Andrew Howroyd, Feb 12 2021
CROSSREFS
KEYWORD
nonn
AUTHOR
Stefan Vigerske, Nov 21 2005
EXTENSIONS
Terms a(21) and beyond from Andrew Howroyd, Feb 12 2021
STATUS
approved