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 A248338 #15 Nov 13 2024 17:15:24
%S A248338 0,6,84,936,9744,98976,995904,9983616,99934464,999737856,9998951424,
%T A248338 99995805696,999983222784,9999932891136,99999731564544,
%U A248338 999998926258176,9999995705032704,99999982820130816,999999931280523264,9999999725122093056,99999998900488372224
%N A248338 a(n) = 10^n - 4^n.
%H A248338 G. C. Greubel, <a href="/A248338/b248338.txt">Table of n, a(n) for n = 0..995</a>
%H A248338 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (14,-40).
%F A248338 G.f.: 6*x/((1-4*x)*(1-10*x)).
%F A248338 a(n) = 14*a(n-1) - 40*a(n-2).
%F A248338 a(n) = 2^n*(5^n - 2^n) = A000079(n) * A005057(n) = A011557(n) - A000302(n).
%F A248338 a(n+1) = 6*A016157(n). [_Bruno Berselli_, Oct 05 2014]
%F A248338 E.g.f.: 2*exp(7*x)*sinh(3*x). - _G. C. Greubel_, Nov 13 2024
%t A248338 Table[10^n - 4^n, {n, 0, 30}] (* or *)
%t A248338 CoefficientList[Series[(6 x)/((1-4 x)(1-10 x)), {x, 0, 30}], x]
%o A248338 (Magma) [10^n-4^n: n in [0..30]];
%o A248338 (PARI) vector(20,n,10^(n-1)-4^(n-1)) \\ _Derek Orr_, Oct 05 2014
%o A248338 (Python)
%o A248338 def A248338(n): return pow(10,n) - pow(4,n)
%o A248338 print([A248338(n) for n in range(41)]) # _G. C. Greubel_, Nov 13 2024
%Y A248338 Cf. A000079, A000302, A005057, A011557, A016157.
%Y A248338 Cf. similar sequences listed in A248337.
%K A248338 nonn,easy
%O A248338 0,2
%A A248338 _Vincenzo Librandi_, Oct 05 2014