1,3

J. Riordan, Enumeration of trees by height and diameter, IBM J. Res. Dev. 4 (1960), 473-478.

N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).

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

Table of n, a(n) for n=1..13.

Index entries for sequences related to trees

Sequence in context: A020962 A027243 A110239 * A217898 A003227 A077848

Adjacent sequences:  A001850 A001851 A001852 * A001854 A001855 A001856

nonn

N. J. A. Sloane.

approved