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A185330 Irregular triangle E(n,g) counting not necessarily connected 3-regular simple graphs on 2n vertices with girth at least g.

%I A185330 #12 Sep 16 2015 04:34:30
%S A185330 1,2,1,6,2,21,6,1,94,23,2,540,112,9,1,4207,801,49,1,42110,7840,455,5,
%T A185330 516344,97723,5784,32,7373924,1436873,90940,385,118573592,23791155,
%U A185330 1620491,7574,1,2103205738,432878091,31478651,181227,3,40634185402
%N A185330 Irregular triangle E(n,g) counting not necessarily connected 3-regular simple graphs on 2n vertices with girth at least g.
%C A185330 The first column is for girth at least 3. The row length is incremented to g-2 when 2n reaches A000066(g).
%H A185330 Jason Kimberley, <a href="/A185330/b185330.txt">Table of i, a(i)=E(n,g) for i = 2..60 (n = 2..16)</a>
%H A185330 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>
%e A185330 1;
%e A185330 2, 1;
%e A185330 6, 2;
%e A185330 21, 6, 1;
%e A185330 94, 23, 2;
%e A185330 540, 112, 9, 1;
%e A185330 4207, 801, 49, 1;
%e A185330 42110, 7840, 455, 5;
%e A185330 516344, 97723, 5784, 32;
%e A185330 7373924, 1436873, 90940, 385;
%e A185330 118573592, 23791155, 1620491, 7574, 1;
%e A185330 2103205738, 432878091, 31478651, 181227, 3;
%e A185330 40634185402, 8544173926, 656784488, 4624502, 21;
%e A185330 847871397424, 181519645163, 14621878339, 122090545, 546, 1;
%e A185330 18987149095005, 4127569521160, 345975756388, 3328929960, 30368, 0;
%Y A185330 Cf. A005638, A185334, A185304.
%K A185330 nonn,hard,tabf
%O A185330 2,2
%A A185330 _Jason Kimberley_, Oct 18 2012