OFFSET
1,9
COMMENTS
Maps are counted up to isomorphism which is not restricted to those that preserve the orientation of the sphere.
REFERENCES
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
Computed by Nick Wormald (unpublished).
LINKS
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, T. R. S. Walsh, personal communication
STATUS
approved