A185364 Not necessarily connected 6-regular simple graphs on n vertices with girth at least 4.

1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 1, 9, 6, 267, 3727, 483012, 69823723, 14836130862

Offset: 0

Author

Jason Kimberley, Dec 07 2011

Keywords

• nonn
• more
• hard

Comments

First differs from A058276 at n=24.

Links

• Jason Kimberley, Not necessarily connected k-regular graphs with girth at least 4
• Jason Kimberley, Index of sequences counting not necessarily connected k-regular simple graphs with girth at least g

Crossrefs

6-regular simple graphs with girth at least 4: A058276 (connected), A185264 (disconnected), this sequence (not necessarily connected).

Not necessarily connected k-regular simple graphs with girth at least 4: A185314 (any k), A185304 (triangle); specified degree k: A008484 (k=2), A185334 (k=3), A185344 (k=4), A185354 (k=5), this sequence (k=6).

Cf. A184964.

Programs

Mathematica

A058276 = Cases[Import["https://oeis.org/A058276/b058276.txt", "Table"], {, }][[All, 2]];
(* EulerTransform is defined in A005195 *)
EulerTransform[Rest @ A058276] (* Jean-François Alcover, Dec 04 2019, updated Mar 18 2020 *)

Formula

This sequence is the Euler transformation of A058276.

a(n) = A058276(n) + A185264(n).