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A032355
Number of connected transitive trivalent (or cubic) graphs with 2n nodes.
7
1, 2, 2, 3, 4, 3, 4, 5, 7, 3, 11, 5, 6, 10, 10, 5, 12, 5, 12, 10, 7, 5, 32, 9, 10, 13, 16, 7, 38, 7, 26, 11, 12, 11, 37, 9, 11, 14, 33, 9, 30, 9, 17, 21, 13, 9, 90, 13, 25, 16, 22, 11, 42, 19, 38, 18, 18, 11, 105, 13, 17, 26, 83, 19, 35, 13, 28, 19, 35, 13, 124, 15, 22, 28, 27, 19, 46, 15, 104, 43, 24, 15, 99, 23, 23, 23, 45, 17, 80, 25, 31, 26, 25, 23, 274, 19, 35, 31, 61, 19
OFFSET
2,2
COMMENTS
Read and Wilson give counts of connected transitive graphs. Gordon Royle states that there are 17 transitive 32-node graphs. Read and Wilson state that 10 of them are connected. - Richard Sabey, Oct 11 2012
REFERENCES
R. C. Read and R. J. Wilson, An Atlas of Graphs, Oxford, 1998.
LINKS
N. J. A. Sloane, Table of n, a(n) for n = 2..640, taken from the work of Primož Potočnik, Pablo Spiga and Gabriel Verret.
Primož Potočnik, Pablo Spiga and Gabriel Verret, A census of small connected cubic vertex-transitive graphs
Gordon Royle, Cubic transitive graphs [Broken link]
Eric Weisstein's World of Mathematics, Cubic Vertex-Transitive Graph
CROSSREFS
Cf. A005638, A002851, A241167 (Euler transf.).
Sequence in context: A259196 A357589 A336200 * A308597 A205153 A300302
KEYWORD
nonn,nice
AUTHOR
Ronald C. Read
EXTENSIONS
"Connected" added by Richard Sabey, Oct 11 2012
Link provided that, in principle, gives values up to n=640. Extended to n=30 from that link by Allan C. Wechsler, Apr 18 2014
Extended to 640 from same source by N. J. A. Sloane, Apr 19 2014
STATUS
approved