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 A152894 #20 Oct 05 2024 03:17:09
%S A152894 0,0,1,4,0,0,0,1,4,0,0,0,1,4,0,0,0,1,4,0,0,0,1,4,0,0,0,1,4,0,0,0,1,4,
%T A152894 0,0,0,1,4,0,0,0,1,4,0,0,0,1,4,0,0,0,1,4,0,0,0,1,4,0,0,0,1,4,0,0,0,1,
%U A152894 4,0,0,0,1,4,0,0,0,1,4,0,0,0,1,4,0,0,0
%N A152894 Periodic sequence [0,0,1,4,0] of period 5.
%H A152894 <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (0,0,0,0,1).
%F A152894 a(n+5) = a(n) with a(0) = a(1) = a(4) = 0, a(2) = 1 and a(3) = 4;
%F A152894 O.g.f.: (z^2+4*z^3)/(1-z^5);
%F A152894 a(n) = 1 + (-1/2 - (1/2)*sqrt(5))*cos(2*n*Pi/5) + (-(3/10)*sqrt(2)*sqrt(5 - sqrt(5)))*sin(2*n*Pi/5) + (-1/2 + (1/2)*sqrt(5))*cos(4*n*Pi/5) + ((3/10)*sqrt(2)*sqrt(5 + sqrt(5)))*sin(4*n*Pi/5).
%F A152894 a(n) = (n^3 - n) mod 5. - _Gary Detlefs_, Mar 20 2010
%p A152894 seq((n^3-n) mod 5,n=0..50); # _Gary Detlefs_, Mar 20 2010
%t A152894 PadRight[{},90,{0,0,1,4,0}] (* _Harvey P. Dale_, Jan 29 2013 *)
%Y A152894 Cf. A026062.
%K A152894 easy,nonn
%O A152894 0,4
%A A152894 _Richard Choulet_, Dec 14 2008