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A046745
Number of connected graphs with <= n edges.
1
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
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
KEYWORD
nonn,nice
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