A046745 Number of connected graphs with <= n edges.

1, 2, 5, 10, 22, 52, 131, 358, 1068, 3390, 11461, 40964, 153786, 603927, 2471798, 10509270, 46296937, 210848414, 990794383, 4795761825, 23875074600, 122086530809, 640484152252, 3443478138871, 18954259427121, 106719731914780, 614115134054991, 3609008134177109

Offset

1,2

Links

Andrew Howroyd, Table of n, a(n) for n = 1..60

G. A. Baker et al., High-temperature expansions for the spin-1/2 Heisenberg model, Phys. Rev., 164 (1967), 800-817.

Mathematica

A000664 = Cases[Import["https://oeis.org/A000664/b000664.txt", "Table"], {_, _}][[All, 2]];
(* EulerInvTransform is defined in A022562 *)
A002905 = EulerInvTransform[Rest@A000664];
Accumulate[A002905] (* Jean-François Alcover, Jul 16 2022 *)

Crossrefs

Partial sums of A002905.

Sequence in context: A232163 A166300 A038149 * A198950 A015902 A301427

Adjacent sequences: A046742 A046743 A046744 * A046746 A046747 A046748

Keyword

nonn,nice

Author

N. J. A. Sloane

Extensions

More terms from Vladeta Jovovic, Apr 10 2001

More terms from Vladeta Jovovic, Jul 05 2003

Terms a(25) and beyond added by Andrew Howroyd, May 06 2021

Status

approved