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 A013750 #25 Sep 08 2022 08:44:38 %S A013750 12,20736,35831808,61917364224,106993205379072,184884258895036416, %T A013750 319479999370622926848,552061438912436417593344, %U A013750 953962166440690129601298432,1648446623609512543951043690496 %N A013750 a(n) = 12^(3*n + 1). %H A013750 Vincenzo Librandi, <a href="/A013750/b013750.txt">Table of n, a(n) for n = 0..200</a> %H A013750 Tanya Khovanova, <a href="http://www.tanyakhovanova.com/RecursiveSequences/RecursiveSequences.html">Recursive Sequences</a> %H A013750 <a href="/index/Rec#order_01">Index entries for linear recurrences with constant coefficients</a>, signature (1728). %F A013750 From _Philippe Deléham_, Nov 30 2008: (Start) %F A013750 a(n) = 1728*a(n-1); a(0)=12. %F A013750 G.f.: 12/(1-1728*x). %F A013750 a(n) = A013751(n)/12. (End) %o A013750 (Magma) [12^(3*n+1): n in [0..15]]; // _Vincenzo Librandi_, Jun 27 2011 %o A013750 (PARI) a(n)=12^(3*n+1) \\ _Charles R Greathouse IV_, Jun 27 2011 %Y A013750 Subsequence of A001021. %K A013750 nonn,easy %O A013750 0,1 %A A013750 _N. J. A. Sloane_