A157051 Number of connected unlabeled non-bipartite graphs on n nodes.

0, 0, 0, 1, 3, 16, 95, 809, 10935, 260350, 11712539, 1006674967, 164059617696, 50335905627489, 29003487431654737, 31397381142185989848, 63969560113210957966315, 245871831682083553779103249, 1787331725248899067681312999794, 24636021429399867654036551645873645, 645465483198722799426625560872826564232

Offset: 0

Author

Max Alekseyev, Feb 22 2009

Keywords

• nonn

Comments

Inverse Euler transform of A157016.

Links

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

Programs

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 *)

Formula

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

Extensions

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