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A364404
Number of (strictly) 1-connected cubic graphs on 2n nodes.
2
0, 0, 0, 0, 1, 4, 29, 186, 1435, 12671, 131820, 1590900, 21940512, 339723835
OFFSET
1,6
LINKS
G. Brinkmann, J. Goedgebeur and B. D. McKay, snarkhunter.
EXAMPLE
For n=5, the unique 10-node cubic graph that is strictly 1-connected is:
o o
/|\ /|\
o-o o-o o-o
\|/ \|/
o o
PROG
(nauty) # The snarkhunter program (see Links) has an option "C2" for (at least) 2-connectivity. So a(n) is the difference between the outputs from "./snarkhunter X 3 ns" and "./snarkhunter X 3 ns C2", where X=2n.
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Ed Wynn, Jul 22 2023
STATUS
approved