A175603 - OEIS

%I #24 Sep 08 2022 08:45:51

%S 40,760,7960,79960,799960,7999960,79999960,799999960,7999999960,

%T 79999999960,799999999960,7999999999960,79999999999960,

%U 799999999999960,7999999999999960,79999999999999960,799999999999999960

%N a(n) = 8*(10^n-5).

%H Vincenzo Librandi, <a href="/A175603/b175603.txt">Table of n, a(n) for n = 1..100</a>

%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (11,-10)

%F G.f.: 40*x*(1+8*x) / ( (10*x-1)*(x-1) ). - _R. J. Mathar_, Aug 24 2011

%t CoefficientList[Series[40 (1 + 8 x)/((10 x - 1) (x - 1)), {x, 0, 30}], x] (* _Vincenzo Librandi_, Oct 05 2014 *)

%t LinearRecurrence[{11,-10},{40,760},20] (* _Harvey P. Dale_, May 12 2022 *)

%o (Magma) [8*(10^n-5): n in [1..30]]; // _Vincenzo Librandi_, Oct 05 2014

%Y Equals 40 * A067272.

%K nonn,easy,less

%O 1,1

%A _Vincenzo Librandi_ Nov 15 2010