3,2

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

C. F. Earl and L. J. March, Architectural applications of graph theory, pp. 327-355 of R. J. Wilson and L. W. Beineke, editors, Applications of Graph Theory. Academic Press, NY, 1979.

Sequence in context: A152876 A153963 A153960 this_sequence A153969 A153966 A138867

Adjacent sequences: A005024 A005025 A005026 this_sequence A005028 A005029 A005030

nonn

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