A339505 Number of non-isomorphic connected cubic cyclic Haar graphs of girth 6 on 2n vertices.

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

Author

Nino Basic, Dec 07 2020

Keywords

• nonn
• more

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.