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A198316
Number of, not necessarily connected, regular simple graphs on n vertices with girth exactly 6.
5
0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 1, 2, 1, 2, 1, 7, 2, 35, 3, 389, 4, 7579, 6, 181233, 9, 4624493, 12, 122090019, 17, 3328899632, 24, 93988911093, 57
OFFSET
0,15
FORMULA
a(n) = A186746(n) + A210716(n).
a(n) = A185316(n) - A185317(n).
CROSSREFS
Not necessarily connected regular simple graphs girth exactly g: A198313 (g=3), A198314 (g=4), A198315 (g=5), this sequence (g=6), A198317 (g=7), A198318 (g=8).
Sequence in context: A016543 A300585 A145999 * A011128 A245595 A146003
KEYWORD
nonn,more,hard
AUTHOR
Jason Kimberley, Dec 13 2012
STATUS
approved