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A316318
Coordination sequence for a node in the graph of Balaban's (3,10)-cage.
1
1, 3, 6, 12, 24, 20, 4
OFFSET
0,2
COMMENTS
The graph has 70 nodes, 105 edges, degree 3, girth 10 and diameter 6.
The automorphism group of this graph has order 80, and has three orbits on nodes, of sizes 40, 20, and 10, respectively. However, the coordination sequence is independent of the choice of the node.
LINKS
A. T. Balaban, A trivalent graph of girth ten, Journal of Combinatorial Theory Series B 12 (1972), 1-5.
M. R. O'Keefe and P. K. Wong, A smallest graph of girth 10 and valency 3, Journal of Combinatorial Theory Series B 29 (1980), 91-105.
N. J. A. Sloane, Balaban's 10-cage, showing 4 disjoint decagons (blue, red, green, yellow) and the three types (A, B, C) of nodes. The labels A, B, C are the same as in Fig. 2 of Balaban's 1972 article.
Eric Weisstein's World of Mathematics, Balaban 10-cage
Wikipedia, Balaban 10-cage [Note that as of Jul 01 2018 this page contains errors. For example, M. R. O'Keefe and P. K. Wong (1980) only assert that there at least three (3,10)-cages. Weisstein's discussion is more accurate. - N. J. A. Sloane, Jul 01 2018]
CROSSREFS
See A250120 for links to thousands of other coordination sequences.
Sequence in context: A215983 A339107 A319445 * A173216 A003204 A038620
KEYWORD
nonn,fini,full
AUTHOR
N. J. A. Sloane, Jul 01 2018
STATUS
approved