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URL: https://oeis.org/A006401

⇱ A006401 - OEIS

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A006401
Number of unsensed simple planar maps with n edges and without vertices of degree 1.
2
1, 0, 0, 1, 1, 2, 5, 10, 28, 86, 285, 1055, 4211
OFFSET
0,6
COMMENTS
A simple planar map is a planar map without loops or parallel edges. - Andrew Howroyd, Jan 16 2025
REFERENCES
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
Timothy R. Walsh, Generating nonisomorphic maps without storing them, SIAM J. Algebraic Discrete Methods 4 (1983), no. 2, 161-178.
CROSSREFS
Cf. A006385, A006389, A006395, A006400 (sensed), A379436 (rooted).
Sequence in context: A257889 A363388 A287963 * A283460 A102964 A075885
KEYWORD
nonn,more
EXTENSIONS
a(11)-a(12) from Sean A. Irvine, Mar 31 2017
a(0)-a(2) prepended by Andrew Howroyd, Jan 16 2025
STATUS
approved