A185959 Number of Cayley graphs on n nodes.

1, 2, 2, 4, 3, 8, 4, 14, 9, 20, 8, 74, 14, 56, 44, 278, 36, 376, 60, 1132, 240, 816, 188, 15394, 464, 4104, 1434, 25784, 1182, 45184, 2192, 659232, 6768, 131660, 11144, 1959040, 14602, 814216, 48462, 13055904, 52488, 9461984, 99880, 39134544, 399126, 34333800, 364724

Offset: 1

Author

Eric W. Weisstein, Feb 07 2011

Keywords

• nonn
• hard

Comments

First differs from A006799 at n = 10.

Links

• Derek Holt and Gordon Royle, A Census of Small Transitive Groups and Vertex-Transitive Graphs, arXiv:1811.09015 [math.CO], 2018.
• G. Royle, Transitive graphs
• Eric Weisstein's World of Mathematics, Cayley Graph

Crossrefs

Row sums of A319372.

Cf. A006792, A006799.

Programs

Mathematica

A006792 = Join[Array[0&, 10], Cases[Import["https://oeis.org/A006792/b006792.txt", "Table"], {, }][[All, 2]]];
A006799 = Cases[Import["https://oeis.org/A006799/b006799.txt", "Table"], {, }][[All, 2]];
a[n_] := A006799[[n]] - A006792[[n+1]];
Array[a, 47] (* Jean-François Alcover, Sep 05 2019 *)

Formula

a(n) = A006799(n) - A006792(n).

Extensions

a(32)-a(47) from Danny Rorabaugh, Nov 26 2018