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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
OFFSET
0,11
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: A373986 A136179 A185176 * A126761 A090559 A088640
KEYWORD
nonn,more,hard
AUTHOR
Jason Kimberley, Dec 13 2012
STATUS
approved