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 A094650 #24 Nov 22 2023 12:16:09
%S A094650 5,-1,9,-4,25,-16,78,-64,257,-256,874,-1013,3034,-3953,10684,-15229,
%T A094650 38017,-58056,136338,-219508,491870,-824737,1782735,-3083887,6484514,
%U A094650 -11489516,23652443,-42688039,86459608,-158270401,316576903,-585868009,1160673633
%N A094650 An accelerator sequence for Catalan's constant.
%H A094650 A. Akbary and Q. Wang, <a href="http://dx.doi.org/10.1155/IJMMS.2005.2631">On some permutation polynomials over finite fields</a>, International Journal of Mathematics and Mathematical Sciences, 2005:16 (2005) 2631-2640.
%H A094650 A. Akbary and Q. Wang, <a href="http://dx.doi.org/10.1090/S0002-9939-05-08220-1">A generalized Lucas sequence and permutation binomials</a>, Proceeding of the American Mathematical Society, 134 (1) (2006), 15-22.
%H A094650 David M. Bradley, <a href="http://dx.doi.org/10.1023/A:1006945407723">A Class of Series Acceleration Formulae for Catalan's Constant</a>, The Ramanujan Journal, Vol. 3, Issue 2, 1999, pp. 159-173
%H A094650 David M. Bradley, <a href="http://arxiv.org/abs/0706.0356">A Class of Series Acceleration Formulae for Catalan's Constant</a>, arXiv:0706.0356 [math.CA], 2007.
%H A094650 Russell A. Gordon, <a href="http://math.colgate.edu/~integers/x84/x84.pdf">Lucas Type Sequences and Sums of Binomial Coefficients</a>, Integers (2023) Vol 23, Art. No. A84. See p. 21.
%H A094650 <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (-1,4,3,-3,-1).
%F A094650 G.f.: (5+4x-12x^2-6x^3+3x^4)/(1+x-4x^2-3x^3+3x^4+x^5).
%F A094650 a(n) = (2*cos(2*Pi/11))^n + (-2*cos(Pi/11))^n + (-2*sin(5*Pi/22))^n +(2*sin(3*Pi/22))^n + (-2*sin(Pi/22))^n.
%t A094650 LinearRecurrence[{-1, 4, 3, -3, -1}, {5, -1, 9, -4, 25}, 33] (* _Jean-François Alcover_, Sep 21 2017 *)
%o A094650 (PARI) Vec((5+4*x-12*x^2-6*x^3+3*x^4)/(1+x-4*x^2-3*x^3+3*x^4+x^5) + O(x^40)) \\ _Michel Marcus_, Jul 25 2015
%Y A094650 Cf. A000032, A094648, A094649.
%K A094650 easy,sign
%O A094650 0,1
%A A094650 _Paul Barry_, May 18 2004