3,3

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

Walsh, T. R. S.; Generating nonisomorphic maps without storing them. SIAM J. Algebraic Discrete Methods 4 (1983), no. 2, 161-178.

Sequence in context: A109621 A075200 A075198 this_sequence A136108 A026297 A109742

Adjacent sequences: A006402 A006403 A006404 this_sequence A006406 A006407 A006408

nonn

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