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 A120634 #13 Dec 24 2015 11:14:20
%S A120634 0,7,6,5,4,11,10,9,8,15,14,13,12,19,18,17,16,23,22,21,20,27,26,25,24,
%T A120634 31,30,29,28,35,34,33,32,39,38,37,36,43,42,41,40,47,46,45,44,51,50,49,
%U A120634 48,55,54,53,52,59,58,57,56,63,62,61,60,67,66,65,64,71,70,69,68,75,74,73
%N A120634 Decimal equivalent of A066335.
%C A120634 The same as A004444 except for first 3 terms. - _Pietro Battiston_, Jan 19 2008
%H A120634 <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (1,0,0,1,-1).
%F A120634 From _Colin Barker_, Oct 06 2014: (Start)
%F A120634 a(n) = (3-(-1)^n-(1-i)*((-i)^n+i*i^n)+n) where i=sqrt(-1).
%F A120634 a(n) = a(n-1)+a(n-4)-a(n-5).
%F A120634 G.f.: -x*(x^3+x^2+x-7) / ((x-1)^2*(x+1)*(x^2+1)).
%F A120634 (End)
%t A120634 LinearRecurrence[{1,0,0,1,-1},{0,7,6,5,4},80] (* _Harvey P. Dale_, May 10 2015 *)
%o A120634 (PARI) concat(0, Vec(-x*(x^3+x^2+x-7)/((x-1)^2*(x+1)*(x^2+1)) + O(x^100))) \\ _Colin Barker_, Oct 06 2014
%Y A120634 Cf. A004444, A066335.
%K A120634 base,easy,nonn
%O A120634 0,2
%A A120634 _Joshua Zucker_, Jun 21 2006