1,3

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

Foulds, L. R.; Robinson, R. W. Enumeration of binary phylogenetic trees. Combinatorial mathematics, VIII (Geelong, 1980), pp. 187-202, Lecture Notes in Math., 884, Springer, Berlin-New York, 1981. Math. Rev. 83a:05071.

Index entries for sequences related to trees

Sequence in context: A018927 A001266 A071971 this_sequence A034471 A100024 A086092

Adjacent sequences: A006677 A006678 A006679 this_sequence A006681 A006682 A006683

nonn

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