%I #13 Mar 06 2020 18:34:59
%S 1,0,1,1,5,13,48,160,578,2078,7658,28467,107096,406290,1553570,
%T 5980040,23154950,90124865,352423336,1383872558,5454586036,
%U 21572961498,85587023964,340518976173,1358341426234,5431524909088,21767112830811,87412948227174,351709144912372
%N A restricted class of multiple edge-free maps on n edges.
%C See Kitaev et al. for precise definition.
%H S. Kitaev, P. Salimov, C. Severs and H. Ulfarsson, <a href="http://staff.ru.is/henningu/papers/maps/maps.pdf">Restricted non-separable planar maps and some pattern avoiding permutations</a>, preprint 2012.
%H S. Kitaev, P. Salimov, C. Severs and H. Ulfarsson, <a href="https://doi.org/10.1016/j.dam.2013.01.004">Restricted non-separable planar maps and some pattern avoiding permutations</a>, Discrete Applied Mathematics, Volume 161, Issues 16-17, November 2013, Pages 2514-2526. See B_3(x).
%F Kitaev et al. give a functional equation that is satisfied by the g.f.
%o (PARI)
%o a(n) = {
%o B = x + O(x^(n+1));
%o for (i=1, n,
%o B = x + B*(B-x) + (B-x)^2 + (B-x-x*B^2)*(B-x) + x*(3*B-2*x-x*B^2)^2; );
%o polcoeff(B, n, x);
%o } \\ _Michel Marcus_, Feb 07 2013
%K nonn
%O 1,5
%A _N. J. A. Sloane_, Jan 01 2013
%E More terms from _Michel Marcus_, Feb 07 2013