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A210713

Number of disconnected regular simple graphs on n vertices with girth exactly 3.

0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 5, 4, 16, 13, 64, 98, 597, 2064, 22472, 112814, 4799607, 31138903, 4207941575, 115979716284, 13482672620149

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OFFSET

0,9

LINKS

Table of n, a(n) for n=0..24.

Jason Kimberley, Index of sequences counting disconnected k-regular simple graphs with girth exactly g

FORMULA

a(n) = A068932(n) - A185214(n).

CROSSREFS

This sequence is the row sum sequence of the triangle A210703.

Disconnected k-regular simple graphs with girth exactly 3: this sequence (any k), A210703 (triangle); for fixed k: A185033 (k=3), A185043 (k=4), A185053 (k=5), A185063 (k=6).

Sequence in context: A284686 A349451 A054079 * A283825 A005177 A357123

Adjacent sequences: A210710 A210711 A210712 * A210714 A210715 A210716

KEYWORD

nonn,more,hard

AUTHOR

Jason Kimberley, Apr 02 2012

STATUS

approved

URL: https://oeis.org/A210713

⇱ A210713 - OEIS