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 A147607 #16 Oct 25 2022 01:38:52
%S A147607 1,0,4,0,12,0,28,0,59,0,116,0,228,0,460,0,968,0,2092,0,4564,0,9908,0,
%T A147607 21309,0,45444,0,96484,0,204700,0,434999,0,926440,0,1976344,0,4218936,
%U A147607 0,9005328,0,19212728,0,40970200,0,87341032,0,186180665,0,396899620
%N A147607 Expansion of g.f.: 1/((1 - 2*x^2 + x^4 + 2*x^6 - x^8)*(1 - 2*x^2 - x^4 + 2*x^6 - x^8)).
%H A147607 G. C. Greubel, <a href="/A147607/b147607.txt">Table of n, a(n) for n = 0..1000</a>
%H A147607 <a href="/index/Rec#order_16">Index entries for linear recurrences with constant coefficients</a>, signature (0,4,0,-4,0,-4,0,11,0,-4,0,-4,0,4,0,-1).
%F A147607 G.f.: 1/(1 - 4*x^2 + 4*x^4 + 4*x^6 - 11*x^8 + 4*x^10 + 4*x^12 - 4*x^14 + x^16).
%F A147607 a(n) = 4*a(n-2) - 4*a(n-4) - 4*a(n-6) + 11*a(n-8) - 4*a(n-10) - 4*a(n-12) + 4*a(n-14) - a(n-16) with a(0)=1, a(1)=0, a(2)=4, a(3)=0, a(4)=12, a(5)=0, a(6)=28, a(7)=0, a(8)=59, a(9)=0, a(10)=116, a(11)=0, a(12)=228, a(13)=0, a(14)=460, a(15)=0. - _Harvey P. Dale_, Apr 03 2013
%F A147607 G.f.: -1/(x^8*f(x)*f(1/x)), where f(x) = -1 + 2*x^2 - x^4 - 2*x^6 + x^8. - _G. C. Greubel_, Oct 24 2022
%t A147607 CoefficientList[Series[1/(1-4 x^2+4 x^4+4 x^6-11 x^8+4 x^10+4 x^12-4 x^14+x^16),{x,0,60}],x] (* or *) LinearRecurrence[ {0,4,0,-4,0,-4,0,11,0,-4,0,-4,0,4,0,-1},{1,0,4,0,12,0,28,0,59,0,116,0,228,0,460,0},60] (* _Harvey P. Dale_, Apr 03 2013 *)
%o A147607 (Magma) R<x>:=PowerSeriesRing(Integers(), 60); Coefficients(R!( 1/((1-2*x^2+x^4 +2*x^6-x^8)*(1-2*x^2-x^4+2*x^6-x^8)) )); // _G. C. Greubel_, Oct 24 2022
%o A147607 (SageMath)
%o A147607 def A147607_list(prec):
%o A147607 P.<x> = PowerSeriesRing(ZZ, prec)
%o A147607 return P( 1/((1-2*x^2+x^4+2*x^6-x^8)*(1-2*x^2-x^4+2*x^6-x^8)) ).list()
%o A147607 A147607_list(60) # _G. C. Greubel_, Oct 24 2022
%Y A147607 Cf. A122584, A147617.
%K A147607 nonn,easy,less
%O A147607 0,3
%A A147607 _Roger L. Bagula_, Nov 08 2008
%E A147607 Definition corrected by _N. J. A. Sloane_, Nov 09 2008