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%I #8 Feb 22 2013 10:46:26
%S 1,1,2,1,2,1,3,2,3,2,3,2,4,3,6,4,7,5,13,7,42,10,398,13,7592,18,181251,
%T 25,4624534,33,122090591,45,3328930034,61,93990693977,106
%N Number of, not necessarily connected, regular simple graphs on n vertices with girth at least 6.
%H Jason Kimberley, <a href="/wiki/User:Jason_Kimberley/E_k-reg_girth_ge_g_index">Index of sequences counting not necessarily connected k-regular simple graphs with girth at least g</a>
%F a(n) = A186726(n) + A185216(n).
%Y Not necessarily connected regular simple graphs with girth at least g: A005176 (g=3), A185314 (g=4), A185315 (g=5), this sequence (g=6), A185317 (g=7), A185318 (g=8), A185319 (g=9).
%K nonn,more,hard
%O 0,3
%A _Jason Kimberley_, Dec 12 2012