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A339505
Number of non-isomorphic connected cubic cyclic Haar graphs of girth 6 on 2n vertices.
0
0, 0, 0, 0, 1, 1, 1, 1, 1, 3, 2, 2, 4, 3, 2, 4, 3, 5, 6, 4, 3, 9, 4, 5, 5, 7, 4, 11
OFFSET
3,10
COMMENTS
a(n) is also the number of connected cyclic configurations of type (n_3)
Sequence A098822 counts all cyclic configurations of type (n_3), while the present sequence counts only those that are connected.
LINKS
N. Bašić, J. Grošelj, B. Grünbaum and T. Pisanski, Splittable and unsplittable graphs and configurations, Ars Math. Contemp. 16 (2019), 1-17.
M. Petkovšek and T. Pisanski, Counting disconnected structures: chemical trees, fullerenes, I-graphs and others, Croatica Chem. Acta 78 (2005), 563-567.
CROSSREFS
Cf. A098822.
Sequence in context: A376310 A372490 A182214 * A373012 A351163 A216161
KEYWORD
nonn,more
AUTHOR
Nino Basic, Dec 07 2020
STATUS
approved