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A198315 Number of, not necessarily connected, regular simple graphs on n vertices with girth exactly 5. 5
0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 2, 1, 3, 1, 9, 2, 50, 3, 453, 5, 5759, 14, 90693, 3926, 1736786, 4132004, 163458044, 4018022167, 119021971966 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,11

LINKS

Table of n, a(n) for n=0..28.

Jason Kimberley, Index of sequences counting not necessarily connected k-regular simple graphs with girth exactly g

FORMULA

a(n) = A186745(n) + A210715(n).

a(n) = A185315(n) - A185316(n).

CROSSREFS

Not necessarily connected regular simple graphs girth exactly g: A198313 (g=3), A198314 (g=4), this sequence (g=5), A198316 (g=6), A198317 (g=7), A198318 (g=8).

Sequence in context: A058036 A136179 A185176 * A126761 A090559 A186725

Adjacent sequences:  A198312 A198313 A198314 * A198316 A198317 A198318

KEYWORD

nonn,more,hard

AUTHOR

Jason Kimberley, Dec 13 2012

STATUS

approved

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Last modified February 20 07:41 EST 2020. Contains 332069 sequences. (Running on oeis4.)