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 A107852 #26 May 03 2024 21:39:09
%S A107852 0,1,2,3,6,7,10,17,22,37,58,83,134,199,298,465,694,1061,1626,2451,
%T A107852 3750,5703,8650,13201,20054,30501,46458,70611,107462,163527,248682,
%U A107852 378449,575734,875813,1332634,2027283,3084262,4692551,7138826,10861073
%N A107852 Expansion of -x*(x^2+1)*(x+1)^2/((2*x^3+x^2-1)*(x^4+1)).
%C A107852 Floretion Algebra Multiplication Program, FAMP Code: 1baseiforzapseq[(.5i' + .5j' + .5'ki' + .5'kj')*(.5'i + .5'j + .5'ik' + .5'jk')], 1vesforzap = A000004
%H A107852 Colin Barker, <a href="/A107852/b107852.txt">Table of n, a(n) for n = 0..1000</a>
%H A107852 <a href="/index/Rec#order_07">Index entries for linear recurrences with constant coefficients</a>, signature (0,1,2,-1,0,1,2).
%F A107852 a(n) = 2*A159284(n) - A091337(n).
%F A107852 a(n) = a(n-2) + 2*a(n-3) - a(n-4) + a(n-6) + 2*a(n-7) for n>6. - _Colin Barker_, Apr 30 2019
%t A107852 CoefficientList[Series[-x(x^2+1)(x+1)^2/((2x^3+x^2-1)(x^4+1)),{x,0, 50}],x] (* or *) LinearRecurrence[ {0,1,2,-1,0,1,2},{0,1,2,3,6,7,10},50] (* _Harvey P. Dale_, May 03 2024 *)
%o A107852 (PARI) a(n)=([0,1,0,0,0,0,0; 0,0,1,0,0,0,0; 0,0,0,1,0,0,0; 0,0,0,0,1,0,0; 0,0,0,0,0,1,0; 0,0,0,0,0,0,1; 2,1,0,-1,2,1,0]^n*[0;1;2;3;6;7;10])[1,1] \\ _Charles R Greathouse IV_, Oct 03 2016
%o A107852 (PARI) concat(0, Vec(x*(1 + x)^2*(1 + x^2) / ((1 - x^2 - 2*x^3)*(1 + x^4)) + O(x^45))) \\ _Colin Barker_, Apr 30 2019
%Y A107852 Cf. A107849, A107850, A107851, A107853.
%K A107852 easy,nonn
%O A107852 0,3
%A A107852 _Creighton Dement_, May 25 2005