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 A010869 #30 Aug 18 2018 21:41:41
%S A010869 30,30,30,30,30,30,30,30,30,30,30,30,30,30,30,30,30,30,30,30,30,30,30,
%T A010869 30,30,30,30,30,30,30,30,30,30,30,30,30,30,30,30,30,30,30,30,30,30,30,
%U A010869 30,30,30,30,30,30,30,30
%N A010869 Constant sequence: a(n) = 30.
%H A010869 Tanya Khovanova, <a href="http://www.tanyakhovanova.com/RecursiveSequences/RecursiveSequences.html">Recursive Sequences</a>
%H A010869 <a href="/index/Di#divseq">Index to divisibility sequences</a>
%H A010869 <a href="/index/Rec#order_01">Index entries for linear recurrences with constant coefficients</a>, signature (1).
%F A010869 a(n) = A007947(A143207(n)). - _Reinhard Zumkeller_, Sep 13 2011
%F A010869 G.f.: 30/(1-x). - _Vincenzo Librandi_, Jan 19 2012
%t A010869 Table[30, {60}] (* _Vincenzo Librandi_, Jan 19 2012 *)
%K A010869 nonn,easy
%O A010869 0,1
%A A010869 _N. J. A. Sloane_