%I M3969 #22 May 01 2014 02:40:01
%S 0,0,0,0,0,0,0,1,1,5,32,385,7573,181224,4624480,122089998,3328899586,
%T 93988909755
%N Number of connected trivalent graphs with 2n nodes and girth exactly 6.
%D CRC Handbook of Combinatorial Designs, 1996, p. 647.
%D Gordon Royle, personal communication.
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H Jason Kimberley, <a href="/wiki/User:Jason_Kimberley/C_k-reg_girth_eq_g_index">Index of sequences counting connected k-regular simple graphs with girth exactly g</a>
%F a(n) = A014374(n) - A014375(n).
%Y Connected 3-regular simple graphs with girth exactly g: A198303 (triangle); specified g: A006923 (g=3), A006924 (g=4), A006925 (g=5), this sequence (g=6), A006927 (g=7).
%Y Connected 3-regular simple graphs with girth at least g: A185131 (triangle); A002851 (g=3), A014371 (g=4), A014372 (g=5), A014374 (g=6), A014375 (g=7), A014376 (g=8).
%K nonn,hard,more
%O 0,10
%A _N. J. A. Sloane_.
%E Definition corrected to include "connected", and "girth at least 6" minus "girth at least 7" formula provided by _Jason Kimberley_, Dec 12 2009