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A187927
Number of embeddings on the sphere of 2-connected planar graphs, minimum vertex degree 3, with n nodes.
3
2, 13, 163, 2067, 30953, 486674, 7957459, 133344454, 2280001754, 39648557743, 699731146514, 12511186297320
OFFSET
6,1
COMMENTS
The graphs are exactly 2-connected, not at least 2-connected. The graphs were enumerated using plantri (by B.D. McKay & G. Brinkmann) for the purpose of finding compound perfect squared squares.
LINKS
Gunnar Brinkmann and Brendan McKay, Plantri Guide
Gunnar Brinkmann and Brendan McKay, Guide to using plantri [Cached copy, with permission]
PROG
(plantri) plantri -p -c2 -m3 -x -u -v n ; or
CROSSREFS
KEYWORD
nonn,more,hard
AUTHOR
Stuart E Anderson, Mar 16 2011
EXTENSIONS
a(15)-a(17) from Lorenz Milla, Oct 08 2013
STATUS
approved