A343872 Number of planar graphs with n edges and no isolated nodes.

1, 1, 2, 5, 11, 26, 68, 177, 497, 1475, 4608, 15188, 52778, 192339, 733676, 2917722, 12052138, 51517308, 227068741, 1028492568

Offset: 0

Author

Andrew Howroyd, May 05 2021

Keywords

• nonn
• more

Comments

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

Crossrefs

Cf. A000664, A005470, A039735, A046091.

Programs

Mathematica

A046091 = Cases[Import["https://oeis.org/A046091/b046091.txt", "Table"], {, }][[All, 2]];
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];
a = etr[A046091[[# + 1]]&];
a /@ Range[0, Length[A046091]-1] (* Jean-François Alcover, Jan 01 2022 *)

Formula

Euler transform of A046091.