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Number of n-edge 3-connected planar maps with a sense-reversing automorphism.
(Formerly M0172)
0

%I M0172 #13 Jan 10 2018 17:19:01

%S 0,0,0,0,0,1,0,1,2,1,4,9,12,27,50,99,188,386,740,1528,3012,6192,12376,

%T 25594,51628,107135,218100,453895,930812,1943281,4009512,8394915,

%U 17414512

%N Number of n-edge 3-connected planar maps with a sense-reversing automorphism.

%C Maps are counted up to isomorphism which is not restricted to those that preserve the orientation of the sphere.

%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

%D Computed by Nick Wormald (unpublished).

%H T. R. S. Walsh, <a href="/A007401/a007401.pdf">Number of sensed planar maps with n edges and m vertices</a>

%K nonn

%O 1,9

%A _N. J. A. Sloane_, T. R. S. Walsh, personal communication