3,2

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

K. L. McAvaney, Counting stable trees, pp. 79-85 of Combinatorial Mathematics (Proceedings 2nd Australian Conf.), Lect. Notes Math. 403, 1974.

K. L. McAvaney, personal communication.

Sequence in context: A004790 A098119 A049959 this_sequence A121050 A089402 A127940

Adjacent sequences: A006542 A006543 A006544 this_sequence A006546 A006547 A006548

nonn

N. J. A. Sloane (njas(AT)research.att.com).