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Number of not necessarily connected 5-regular simple graphs on 2n vertices with girth exactly 3.
6

%I #11 May 01 2014 02:37:07

%S 0,0,0,1,3,59,7848,3459379,2585136353,2807104852102

%N Number of not necessarily connected 5-regular simple graphs on 2n vertices with girth exactly 3.

%H Jason Kimberley, <a href="/wiki/User:Jason_Kimberley/E_k-reg_girth_eq_g_index">Index of sequences counting not necessarily connected k-regular simple graphs with girth exactly g</a>

%F a(n) = A165626(n) - A185354(n).

%F a(n) = A184953(n) + A185053(n).

%Y 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).

%K nonn,hard,more

%O 0,5

%A _Jason Kimberley_, Mar 12 2012