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 A152835 #21 Mar 15 2024 02:22:22
%S A152835 -22,23,-21,24,-20,25,-19,26,-18,27,-17,28,-16,29,-15,30,-14,31,-13,
%T A152835 32,-12,33,-11,34,-10,35,-9,36,-8,37,-7,38,-6,39,-5,40,-4,41,-3,42,-2,
%U A152835 43,-1,44,0,45,1,46,2,47,3,48,4,49,5,50,6,51,7,52,8,53,9,54,10,55,11,56,12
%N A152835 a(0) = -22; a(n) = n-a(n-1).
%H A152835 Colin Barker, <a href="/A152835/b152835.txt">Table of n, a(n) for n = 0..1000</a>
%H A152835 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (1,1,-1).
%F A152835 a(n) = a(n-1)+a(n-2)-a(n-3). G.f.: -(22*x^2-45*x+22) / ((x-1)^2*(x+1)). - _Colin Barker_, Oct 28 2014
%p A152835 A152835:=n->(1-89*(-1)^n+2*n)/4: seq(A152835(n), n=0..100); # _Wesley Ivan Hurt_, Oct 28 2014
%t A152835 lst={};a=-22;Do[a=n-a;AppendTo[lst,a],{n,0,6!}];lst
%o A152835 (PARI) Vec(-(22*x^2-45*x+22)/((x-1)^2*(x+1)) + O(x^100)) \\ _Colin Barker_, Oct 28 2014
%o A152835 (Magma) [(1-89*(-1)^n+2*n)/4 : n in [0..100]]; // _Wesley Ivan Hurt_, Oct 28 2014
%Y A152835 Cf. A084964, A152832, A152833.
%K A152835 sign,easy
%O A152835 0,1
%A A152835 _Vladimir Joseph Stephan Orlovsky_, Dec 14 2008
%E A152835 Indices added to definition, offset corrected - _R. J. Mathar_, Jan 08 2009
%E A152835 Name and Mathematica code corrected by _Colin Barker_, Oct 28 2014