This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A006925 M1879 #25 Jul 08 2025 16:57:55 %S A006925 0,0,0,0,0,1,2,8,48,450,5751,90553,1612905,31297357,652159389, %T A006925 14499780660,342646718608 %N A006925 Number of connected trivalent graphs with 2n nodes and girth exactly 5. %D A006925 CRC Handbook of Combinatorial Designs, 1996, p. 647. %D A006925 Gordon Royle, personal communication. %D A006925 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %H A006925 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 A006925 a(n) = A014372(n) - A014374(n). %Y A006925 Connected k-regular simple graphs with girth exactly 5: this sequence (k=3), A184945 (k=4), A184955 (k=5). %Y A006925 Connected 3-regular simple graphs with girth exactly g: A198303 (triangle); specified g: A006923 (g=3), A006924 (g=4), this sequence %Y A006925 (g=5), A006926 (g=6), A006927 (g=7). %Y A006925 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 A006925 nonn,hard,more %O A006925 0,7 %A A006925 _N. J. A. Sloane_ %E A006925 Definition corrected to include "connected", and "girth at least 5" minus "girth at least 6" formula provided by _Jason Kimberley_, Dec 12 2009