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A185153
Number of not necessarily connected 5-regular simple graphs on 2n vertices with girth exactly 3.
6
0, 0, 0, 1, 3, 59, 7848, 3459379, 2585136353, 2807104852102
OFFSET
0,5
FORMULA
a(n) = A165626(n) - A185354(n).
a(n) = A184953(n) + A185053(n).
CROSSREFS
Not necessarily connected k-regular simple graphs girth exactly 3: A198313 (any k), A185643 (triangle); fixed k: A026796 (k=2), A185133 (k=3), A185143 (k=4), this sequence (k=5), A185163 (k=6).
Sequence in context: A369949 A062629 A184953 * A215609 A360837 A201184
KEYWORD
nonn,hard,more
AUTHOR
Jason Kimberley, Mar 12 2012
STATUS
approved