|
%I #14 May 01 2014 02:37:07
%S 0,0,1,1,4,15,71,428,3406,34270,418621,5937051,94782437,1670327647,
%T 32090011476,666351752261,14859579573845
%N Number of not necessarily connected 3-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) = A005638(n) - A185334(n).
%F a(n) = A006923(n) + A185033(n).
%Y Not necessarily connected k-regular simple graphs girth exactly 3: A198313 (any k), A185643 (triangle); fixed k: A026796 (k=2), this sequence (k=3), A185143 (k=4), A185153 (k=5), A185163 (k=6).
%Y Not necessarily connected 3-regular simple graphs on 2n vertices with girth exactly g: A185130 (triangle); fixed g: this sequence (g=3), A185134 (g=4), A185135 (g=5), A185136 (g=6).
%K nonn,hard,more
%O 0,5
%A _Jason Kimberley_, Mar 21 2012
|
