1,2

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

N. C. Wormald, Triangles in labeled cubic graphs, pp. 337-345 of Combinatorial Mathematics (Canberra, 1977), Lect. Notes Math. 686, 1978.

R. W. Robinson, Numerical implementation of graph counting algorithms, AGRC Grant, Math. Dept., Univ. Newcastle, Australia, 1977.

R. W. Robinson, Table of n, a(n) for n = 1..29

Sequence in context: A068204 A001332 A071304 this_sequence A062081 A053881 A075114

Adjacent sequences: A006604 A006605 A006606 this_sequence A006608 A006609 A006610

nonn

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