A185264 - OEIS

A185264

Number of disconnected 6-regular simple graphs on n vertices with girth at least 4.

0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 1, 10, 7, 277, 3742, 483330, 69827771, 14836620025

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,29

LINKS

FORMULA

a(n)

= Euler_transformation(A058276)(n) - A058276(n).

CROSSREFS

6-regular simple graphs with girth at least 4: A058276 (connected), this sequence (disconnected), A185364 (not necessarily connected).

Disconnected k-regular simple graphs with girth at least 4: A185214 (any k), A185204 (triangle); specified degree k: A185224 (k=2), A185234 (k=3), A185244 (k=4), A185254 (k=5), this sequence (k=6), A185274 (k=7), A185284 (k=8), A185294 (k=9).

KEYWORD

nonn,more,hard

AUTHOR

STATUS

approved