0,2

F. Bergeron, G. Labelle and P. Leroux, Combinatorial Species and Tree-Like Structures, Camb. 1998, p. 307.

Cf. A058927.

Sequence in context: A003275 A078558 A003032 this_sequence A004141 A009693 A104190

Adjacent sequences: A058925 A058926 A058927 this_sequence A058929 A058930 A058931

nonn,frac,easy,more

N. J. A. Sloane (njas(AT)research.att.com), Jan 12 2001