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%I M3086 #18 May 01 2014 02:40:01
%S 0,0,0,0,0,0,0,0,0,0,0,0,1,3,21,545,30368,1782839,95079080,4686063107
%N Number of connected trivalent graphs with 2n nodes and girth exactly 7.
%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) = A014375(n) - A014376(n).
%Y Connected 3-regular simple graphs with girth exactly g: A198303 (triangle); specified g: A006923 (g=3), A006924 (g=4), A006925 (g=5), A006926 (g=6), this sequence (g=7).
%Y Connected 3-regular simple graphs with girth at least g: A002851 (g=3), A014371 (g=4), A014372 (g=5), A014374 (g=6), A014375 (g=7), A014376 (g=8).
%K nonn,hard,more
%O 0,14
%A _N. J. A. Sloane_.
%E Definition amended to include "connected" (no disconnected yet), and "girth at least 7" minus "girth at least 8" formula provided by _Jason Kimberley_, Dec 12 2009
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