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 A006824 M3493 #21 Apr 03 2020 21:53:21 %S A006824 1,1,4,14,129,1980,62611,2806490,158937213,10773251972,855658082615, %T A006824 78558949838723,8251166737356319,982806379842257309, %U A006824 131756174189661102281,19748565896506014747623,3289970433888731383271400,605948436052375098046655323,122796503871896458570959144266 %N A006824 Number of connected regular bipartite graphs of degree 4 with 2n nodes. %D A006824 CRC Handbook of Combinatorial Designs, 1996, p. 648. %D A006824 I. A. Faradzev, Constructive enumeration of combinatorial objects, pp. 131-135 of Problèmes combinatoires et théorie des graphes (Orsay, 9-13 Juillet 1976). Colloq. Internat. du C.N.R.S., No. 260, Centre Nat. Recherche Scient., Paris, 1978. %D A006824 H. Gropp, On tactical configurations, regular bipartite graphs and (v,k,even)-designs, Discr. Math., 155 (1996), 81-98. %D A006824 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %H A006824 B. D. McKay and E. Rogoyski, <a href="http://www.combinatorics.org/Volume_2/volume2.html#N3">Latin squares of order ten</a>, Electron. J. Combinatorics, 2 (1995) #N3. %H A006824 M. Meringer, <a href="http://www.mathe2.uni-bayreuth.de/markus/reggraphs.html">Tables of Regular Graphs</a> %F A006824 Inverse Euler transform of A333730. - _Andrew Howroyd_, Apr 03 2020 %Y A006824 Column 4 of A008326. %Y A006824 Cf. A006823, A006825, A333730. %K A006824 nonn,hard,nice %O A006824 4,3 %A A006824 _N. J. A. Sloane_ %E A006824 Terms a(12) and beyond from _Andrew Howroyd_, Apr 03 2020