A006388 Number of sensed planar maps with n edges and without faces of degree 1.
1, 1, 2, 6, 18, 74, 393, 2282, 14700, 99614, 703519, 5123598, 38279496
Offset: 0
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.
Extensions
a(8)-a(12) from Sean A. Irvine, Mar 28 2017
a(0)=1 prepended by Andrew Howroyd, Jan 16 2025