

A185314


Number of, not necessarily connected, regular simple graphs on n vertices with girth at least 4.


16



1, 1, 2, 1, 3, 2, 4, 2, 7, 3, 14, 6, 44, 37, 350, 1616, 18042, 193919, 2867779, 32674078, 1581632332, 6705889886
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OFFSET

0,3


LINKS

Table of n, a(n) for n=0..21.
Jason Kimberley, Not necessarily connected kregular graphs with girth at least 4
Jason Kimberley, Index of sequences counting not necessarily connected kregular simple graphs with girth at least g


FORMULA

a(n) = A186724(n) + A185214(n).
a(n) is the sum of the nth row of A185304.


CROSSREFS

Regular graphs, of any degree, with girth at least 4: A186724 (connected), A185214 (disconnected), this sequence (notnecessarily connected).
Not necessarily connected kregular simple graphs with girth at least 4: this sequence (any k), A185304 (triangle); specified degree k: A008484 (k=2), A185334 (k=3), A185344 (k=4), A185354 (k=5), A185364 (k=6).
Not necessarily connected regular simple graphs with girth at least g: A005176 (g=3), this sequence (g=4), A185315 (g=5), A185316 (g=6), A185317 (g=7), A185318 (g=8), A185319 (g=9).
Sequence in context: A294199 A078658 A307719 * A285120 A282744 A195310
Adjacent sequences: A185311 A185312 A185313 * A185315 A185316 A185317


KEYWORD

nonn,more,hard


AUTHOR

Jason Kimberley, May 23 2012


STATUS

approved



