The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A185334

(Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A185334

Number of not necessarily connected 3-regular simple graphs on 2n vertices with girth at least 4.
(history; published version)

#32 by Susanna Cuyler at Wed Mar 18 09:00:51 EDT 2020

STATUS

reviewed

approved

#31 by Joerg Arndt at Wed Mar 18 07:50:00 EDT 2020

STATUS

proposed

reviewed

#30 by Jean-François Alcover at Wed Mar 18 06:40:11 EDT 2020

STATUS

editing

proposed

#29 by Jean-François Alcover at Wed Mar 18 06:40:06 EDT 2020

MATHEMATICA

etr[f_] := Module[{b}, b[n_] := b[n] = If[n == 0, 1, Sum[Sum[d f[d], {d, Divisors[j]}] b[n - j], {j, 1, n}]/n]; b];

a = etr[A014371[[# + 1]]&];

(* EulerTransform is defined in A005195 *)

a /@ Range[0, LengthEulerTransform[Rest @ A014371] - 1] (* Jean-François Alcover, Dec 04 2019 , updated Mar 18 2020 *)

STATUS

approved

editing

#28 by Susanna Cuyler at Wed Dec 04 21:02:46 EST 2019

STATUS

proposed

approved

#27 by Jean-François Alcover at Wed Dec 04 08:49:36 EST 2019

STATUS

editing

proposed

#26 by Jean-François Alcover at Wed Dec 04 08:49:32 EST 2019

MATHEMATICA

A014371 = Cases[Import["https://oeis.org/A014371/b014371.txt", "Table"], {_, _}][[All, 2]];

etr[f_] := Module[{b}, b[n_] := b[n] = If[n == 0, 1, Sum[Sum[d f[d], {d, Divisors[j]}] b[n - j], {j, 1, n}]/n]; b];

a = etr[A014371[[# + 1]]&];

a /@ Range[0, Length[A014371] - 1] (* Jean-François Alcover, Dec 04 2019 *)

STATUS

approved

editing

#25 by Alois P. Heinz at Thu Oct 24 18:49:00 EDT 2013

STATUS

editing

approved

#24 by Alois P. Heinz at Thu Oct 24 18:48:56 EDT 2013

AUTHOR

_Jason Kimberley, _, Feb 15 2011.

STATUS

approved

editing

#23 by Joerg Arndt at Sat Jan 19 11:38:15 EST 2013

STATUS

reviewed

approved