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Number of planar graphs with n edges and no isolated nodes.
1

%I #10 Jan 01 2022 15:40:18

%S 1,1,2,5,11,26,68,177,497,1475,4608,15188,52778,192339,733676,2917722,

%T 12052138,51517308,227068741,1028492568

%N Number of planar graphs with n edges and no isolated nodes.

%C The first difference between this sequence and A000664 is for n=9 edges where we see K_{3,3}, the "utility graph".

%F Euler transform of A046091.

%t A046091 = Cases[Import["https://oeis.org/A046091/b046091.txt", "Table"], {_, _}][[All, 2]];

%t etr[f_] := Module[{b}, b[n_] := b[n] = If[n == 0, 1, Sum[Sum[d f[d], {d, Divisors[j]}] b[n - j], {j, 1, n}]/n]; b];

%t a = etr[A046091[[# + 1]]&];

%t a /@ Range[0, Length[A046091]-1] (* _Jean-François Alcover_, Jan 01 2022 *)

%Y Cf. A000664, A005470, A039735, A046091.

%K nonn,more

%O 0,3

%A _Andrew Howroyd_, May 05 2021