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 A020525 #18 Jun 13 2015 00:48:54
%S A020525 1,3,847,45375,1770751,61871103,2063618047,67377381375,2177548746751,
%T A020525 70025148104703,2246302260789247,71969633128677375,
%U A020525 2304435634414026751,73764458297036898303,2360822953465975144447,75552099118396657893375
%N A020525 a(n) = 5th Euler polynomial evaluated at 2^n and multiplied by 2.
%H A020525 Colin Barker, <a href="/A020525/b020525.txt">Table of n, a(n) for n = 0..664</a>
%H A020525 <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (53,-756,2752,-2048).
%F A020525 a(n) = 53*a(n-1)-756*a(n-2)+2752*a(n-3)-2048*a(n-4) for n>3. - _Colin Barker_, May 04 2015
%F A020525 G.f.: (1444*x^2-50*x+1) / ((x-1)*(4*x-1)*(16*x-1)*(32*x-1)). - _Colin Barker_, May 04 2015
%p A020525 seq(euler(5,2**i),i=0..24);
%t A020525 Table[EulerE[5,2^n],{n,0,40}]*2 (* _Vladimir Joseph Stephan Orlovsky_, Nov 03 2009 *)
%o A020525 (PARI) Vec((1444*x^2-50*x+1)/((x-1)*(4*x-1)*(16*x-1)*(32*x-1)) + O(x^100)) \\ _Colin Barker_, May 04 2015
%Y A020525 Cf. A020523 - A020526.
%K A020525 nonn,easy
%O A020525 0,2
%A A020525 _Simon Plouffe_