A210717 - OEIS

%I #4 Dec 18 2012 11:14:44

%S 0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,2,2,3,3,4,4,5,6,7,8,10,11,

%T 13,15,18,20,24,27,32,36,42,48,56,63,73,83,96,109,125,144,162,210,209,

%U 845,270,32541,346,1885800,443,101215159,565,5025321572

%N Number of disconnected regular simple graphs on n vertices with girth exactly 7.

%H Jason Kimberley, <a href="/wiki/User:Jason_Kimberley/D_k-reg_girth_eq_g_index">Index of sequences counting disconnected k-regular simple graphs with girth exactly g</a>

%F a(n) = A185217(n) - A185218(n).

%K nonn,more,hard

%O 0,22

%A _Jason Kimberley_, Dec 18 2012