A006439 - OEIS

%I M3719 #11 Apr 04 2021 13:44:44

%S 4,152,2630,31500,303534,2530976,19030428,132386340,866782510,

%T 5405853200

%N Number of tree-rooted toroidal maps with 2 faces and n vertices and without separating loops.

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

%H T. R. S. Walsh and A. B. Lehman, <a href="http://dx.doi.org/10.1016/0095-8956(75)90050-7">Counting rooted maps by genus. III: Nonseparable maps</a>, J. Combinatorial Theory Ser. B 18 (1975), 222-259.

%Y Cf. A006440.

%K nonn,more

%O 1,1

%A _N. J. A. Sloane_

%E Name clarified by _Andrew Howroyd_, Apr 04 2021