A210715 Number of disconnected regular simple graphs on n vertices with girth exactly 5.

0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 2, 2, 3, 3, 4, 6, 6, 9, 9, 22, 13, 82, 18, 618, 26, 7164, 36, 107862, 50, 1876730, 70, 35924810, 95, 741405213, 131, 16356067216, 323, 383931367731, 132977

Offset

0,16

Links

Table of n, a(n) for n=0..43.

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

Formula

a(n) = A185215(n) - A185216(n).

Crossrefs

Sequence in context: A078935 A276774 A129768 * A072926 A080087 A345163

Adjacent sequences: A210712 A210713 A210714 * A210716 A210717 A210718

Keyword

nonn,more,hard

Author

Jason Kimberley, Dec 10 2012

Status

approved