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%I #35 Jun 29 2023 12:30:19
%S 5,20,100,500,2500,12500,62500,312500,1562500,7812500,39062500,
%T 195312500,976562500,4882812500,24414062500,122070312500,610351562500,
%U 3051757812500,15258789062500,76293945312500,381469726562500
%N a(1)=5. For n > 1, a(n) = 4*5^(n-1) = A005054(n).
%C a(n) is the number of n-digit integers that contain only even digits (A014263). - _Bernard Schott_, Nov 11 2022
%H G. C. Greubel, <a href="/A110595/b110595.txt">Table of n, a(n) for n = 1..1000</a>
%H <a href="/index/Rec#order_01">Index entries for linear recurrences with constant coefficients</a>, signature (5).
%F O.g.f.: 5*x*(1-x)/(1-5*x). - Better definition from _R. J. Mathar_, May 13 2008
%F Sum_{n>=1} 1/a(n) = 21/80. - _Bernard Schott_, Nov 11 2022
%t Join[{5},NestList[5#&,20,20]] (* _Harvey P. Dale_, Jun 19 2013 *)
%t Rest[CoefficientList[Series[5 x (1 - x)/(1 - 5 x), {x,0,50}], x]] (* _G. C. Greubel_, Sep 01 2017 *)
%o (PARI) my(x='x+O('x^50)); Vec(5*x*(1-x)/(1-5*x)) \\ _G. C. Greubel_, Sep 01 2017
%Y Cf. A000351, A007091, A014263, A081604, A110591, A110592, A110593, A110594.
%K easy,less,nonn
%O 1,1
%A _Jonathan Vos Post_, Jul 29 2005
%E Better definition from _R. J. Mathar_, May 13 2008
%E Incorrect comment removed by _Michel Marcus_, Nov 11 2022
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