1,2

Probably an incorrect version of A000421.

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

A. T. Balaban, Enumeration of Cyclic Graphs, pp. 63-105 of A. T. Balaban, ed., Chemical Applications of Graph Theory, Ac. Press, 1976; see p. 92.

Sequence in context: A000666 A027321 A027315 this_sequence A000421 A009244 A104985

Adjacent sequences: A005962 A005963 A005964 this_sequence A005966 A005967 A005968

nonn

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