%I M1279 #32 Dec 19 2021 00:07:56
%S 1,2,4,14,52,248,1416,9172,66366,518868,4301350,37230364,333058463,
%T 3057319072,28656583950,273298352168,2645186193457,25931472185976
%N Number of connected planar maps with n edges.
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%D T. R. S. Walsh, personal communication.
%H Richard Kapolnai, Gabor Domokos, and Timea Szabo, <a href="http://arxiv.org/abs/1206.1698">Generating spherical multiquadrangulations by restricted vertex splittings and the reducibility of equilibrium classes</a>, Periodica Polytechnica Electrical Engineering, 56(1):11-10, 2012. Also arXiv:1206.1698, 2012. See Table 2.
%H V. A. Liskovets, <a href="http://dx.doi.org/10.1016/0012-365X(94)00347-L">A reductive technique for enumerating nonisomorphic planar maps</a>, Discr. Math., v.156 (1996), 197-217.
%H Walsh, T. R. S., <a href="https://doi.org/10.1137/0604018">Generating nonisomorphic maps without storing them</a>, SIAM J. Algebraic Discrete Methods 4 (1983), no. 2, 161-178.
%H Timothy R. Walsh, <a href="http://www.info2.uqam.ca/~walsh_t/papers/GENERATING NONISOMORPHIC.pdf">Space-efficient generation of nonisomorphic maps and hypermaps</a>
%H T. R. Walsh, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL18/Walsh/walsh3.html">Space-Efficient Generation of Nonisomorphic Maps and Hypermaps</a>, J. Int. Seq. 18 (2015) # 15.4.3
%H Wormald, Nicholas C. <a href="http://dx.doi.org/10.1016/0012-365X(81)90238-7">Counting unrooted planar maps</a>, Discrete Math. 36 (1981), no. 2, 205-225.
%Y Cf. A090376.
%Y Cf. A006387, A214814, A214815, A214816.
%K nonn,nice
%O 0,2
%A _N. J. A. Sloane_