OFFSET
0,2
COMMENTS
Sequence C_n(4) in Riordan 1978 or 1979.
LINKS
John Riordan, Forests of label-increasing trees, annotated scanned copy of 1978 pre-publication version.
John Riordan, Forests of label-increasing trees, J. Graph Theory, 3 (1979), 127-133.
FORMULA
E.g.f.: F(x)^2, where F(x) is the e.g.f. for A297200. - Max Alekseyev, Jul 12 2019
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Jan 10 2018
EXTENSIONS
Edited and more terms added by Max Alekseyev, Jul 12 2019
STATUS
approved