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A059282
Number of symmetric trivalent (or cubic) connected graphs on 2n nodes (the Foster census).
2
0, 1, 1, 1, 1, 0, 1, 1, 1, 2, 0, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 0, 0, 1, 1, 0, 1, 3, 0, 1, 1, 1, 0, 0, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 0, 0, 2, 2, 0, 1, 1, 0, 1, 1, 3, 1, 0, 0, 2, 1, 0, 1, 2, 0, 0, 1, 0, 0, 0, 0, 2, 1, 0, 1, 1, 0, 0, 1, 0, 3, 0, 0, 6, 0, 0, 0, 0, 0, 0, 4, 0, 1, 0, 0, 3, 1, 0, 0, 1, 0, 1, 1, 1, 0, 0, 0, 3, 1, 3, 1, 3, 0, 0, 0, 0, 2, 0, 0, 3, 1, 0, 0, 1, 1, 0, 1, 4, 1, 0, 0, 0, 2, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 2, 0, 0, 2, 1, 0, 0, 1
OFFSET
1,10
COMMENTS
Potočnik et al. refer to these as arc-transitive connected cubic vertex-transitive graphs.
Marston Conder (Email to N. J. A. Sloane, May 08 2017) remarks that "the first 5000 terms of A091430 are the same as the first 5000 terms of this sequence, with the exception of the 5th and 14th terms (corresponding to the Petersen graph and the Coxeter graph). I verified this soon after completing the determination of all connected symmetric 3-valent graphs of order up to 10000, in June 2011."
REFERENCES
I. Z. Bouwer, W. W. Chernoff, B. Monson and Z. Star, The Foster Census (Charles Babbage Research Centre, 1988), ISBN 0-919611-19-2.
LINKS
Marston Conder, Table of n, a(n) for n = 1..5000 [The first 640 terms were added by N. J. A. Sloane, based on the work of Primož Potočnik, Pablo Spiga and Gabriel Verret]
Marston Conder, Home Page (Contains tables of regular maps, hypermaps and polytopes, trivalent symmetric graphs, and surface actions)
Marston Conder and P. Dobcsányi, Trivalent symmetric graphs on up to 768 vertices, J. Combinatorial Mathematics & Combinatorial Computing 40 (2002), 41-63.
Primož Potočnik, Pablo Spiga and Gabriel Verret, A census of small connected cubic vertex-transitive graphs (See the sub-page Table.html) [Broken link]
Gordon Royle et al., Cubic symmetric graphs (The Foster Census) [Broken link]
Eric Weisstein's World of Mathematics, Cubic Symmetric Graph
EXAMPLE
The first example is K_4 with 4 nodes, thus a(2) = 1.
CROSSREFS
KEYWORD
nonn,nice
AUTHOR
N. J. A. Sloane, Jan 24 2001
EXTENSIONS
Updated all links. Corrected entries based on the Potočnik et al. table. - N. J. A. Sloane, Apr 19 2014
STATUS
approved