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Number of Cayley graphs on n nodes.
7

%I #20 Sep 05 2019 10:41:30

%S 1,2,2,4,3,8,4,14,9,20,8,74,14,56,44,278,36,376,60,1132,240,816,188,

%T 15394,464,4104,1434,25784,1182,45184,2192,659232,6768,131660,11144,

%U 1959040,14602,814216,48462,13055904,52488,9461984,99880,39134544,399126,34333800,364724

%N Number of Cayley graphs on n nodes.

%C First differs from A006799 at n = 10.

%H Derek Holt and Gordon Royle, <a href="https://arxiv.org/abs/1811.09015">A Census of Small Transitive Groups and Vertex-Transitive Graphs</a>, arXiv:1811.09015 [math.CO], 2018.

%H G. Royle, <a href="http://staffhome.ecm.uwa.edu.au/~00013890/remote/trans/index.html">Transitive graphs</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/CayleyGraph.html">Cayley Graph</a>

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

%t A006792 = Join[Array[0&, 10], Cases[Import["https://oeis.org/A006792/b006792.txt", "Table"], {_, _}][[All, 2]]];

%t A006799 = Cases[Import["https://oeis.org/A006799/b006799.txt", "Table"], {_, _}][[All, 2]];

%t a[n_] := A006799[[n]] - A006792[[n+1]];

%t Array[a, 47] (* _Jean-François Alcover_, Sep 05 2019 *)

%Y Row sums of A319372.

%Y Cf. A006792, A006799.

%K nonn,hard

%O 1,2

%A _Eric W. Weisstein_, Feb 07 2011

%E a(32)-a(47) from _Danny Rorabaugh_, Nov 26 2018