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A157051 Number of connected unlabeled non-bipartite graphs on n nodes. 3
0, 0, 0, 1, 3, 16, 95, 809, 10935, 260350, 11712539, 1006674967, 164059617696, 50335905627489, 29003487431654737, 31397381142185989848, 63969560113210957966315, 245871831682083553779103249, 1787331725248899067681312999794, 24636021429399867654036551645873645, 645465483198722799426625560872826564232 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,5

COMMENTS

Inverse Euler transform of A157016.

LINKS

Andrew Howroyd, Table of n, a(n) for n = 0..50

FORMULA

a(n) = A001349(n) - A005142(n).

MATHEMATICA

A001349 = Cases[Import["https://oeis.org/A001349/b001349.txt", "Table"], {_, _}][[All, 2]];

A005142 = Cases[Import["https://oeis.org/A005142/b005142.txt", "Table"], {_, _}][[All, 2]];

a[n_] := A001349[[n + 1]] - A005142[[n + 1]];

a /@ Range[0, 50] (* Jean-François Alcover, Sep 21 2019 *)

CROSSREFS

Sequence in context: A181067 A006347 A000270 * A000271 A157016 A228792

Adjacent sequences:  A157048 A157049 A157050 * A157052 A157053 A157054

KEYWORD

nonn

AUTHOR

Max Alekseyev, Feb 22 2009

EXTENSIONS

a(0) corrected, a(18)-a(20) added by Max Alekseyev, Jun 24 2013

STATUS

approved

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Last modified April 8 18:47 EDT 2020. Contains 333323 sequences. (Running on oeis4.)