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A186743
Number of connected regular simple graphs on n vertices with girth exactly 3.
2
0, 0, 0, 1, 1, 1, 3, 3, 13, 21, 157, 536, 18942, 389404, 50314456, 2942196832, 1698517018391
OFFSET
0,7
FORMULA
a(n) = A005177(n) - A186724(n).
CROSSREFS
Connected k-regular simple graphs with girth exactly 3: this sequence (any k), A186733 (triangular array); specified k: A006923 (k=3),A184943 (k=4), A184953 (k=5), A184963 (k=6), A184973 (k=7),A184983 (k=8), A184993 (k=9).
Sequence in context: A095336 A072552 A217246 * A219314 A288146 A019154
KEYWORD
nonn,more,hard
AUTHOR
Jason Kimberley, Dec 01 2011
STATUS
approved