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 A093136 #32 May 08 2023 02:24:27
%S A093136 1,2,20,200,2000,20000,200000,2000000,20000000,200000000,2000000000,
%T A093136 20000000000,200000000000,2000000000000,20000000000000,
%U A093136 200000000000000,2000000000000000,20000000000000000,200000000000000000,2000000000000000000,20000000000000000000
%N A093136 Expansion of (1 - 8*x)/(1 - 10*x).
%C A093136 A convex combination of 10^n and 0^n.
%C A093136 Inverse binomial transform of A083294. - _Stefano Spezia_, Jul 07 2021
%H A093136 <a href="/index/Rec#order_01">Index entries for linear recurrences with constant coefficients</a>, signature (10).
%F A093136 a(n) = (2*10^n + 8*0^n)/10.
%F A093136 a(n) = 2*10^(n-1), n > 0. - _Vincenzo Librandi_, Aug 02 2010
%F A093136 E.g.f.: (8 + 2*exp(10*x))/10. - _Stefano Spezia_, Jul 05 2021
%F A093136 From _Amiram Eldar_, May 08 2023: (Start)
%F A093136 Sum_{n>=0} 1/a(n) = 14/9.
%F A093136 Sum_{n>=0} (-1)^n/a(n) = 6/11.
%F A093136 Product_{n>=1} (1 - 1/a(n)) = A132026. (End)
%t A093136 CoefficientList[Series[(1-8x)/(1-10x),{x,0,30}],x] (* or *) LinearRecurrence[{10},{1,2},30] (* _Harvey P. Dale_, Oct 02 2022 *)
%o A093136 (PARI) Vec((1-8*x)/(1-10*x) + O(x^20)) \\ _Felix Fröhlich_, Jul 07 2021
%Y A093136 Partial sums are A093135.
%Y A093136 Cf. A083294, A132026.
%K A093136 easy,nonn
%O A093136 0,2
%A A093136 _Paul Barry_, Mar 24 2004