%I #17 Jun 30 2023 15:19:20
%S 6,186,1986,19986,199986,1999986,19999986,199999986,1999999986,
%T 19999999986,199999999986,1999999999986,19999999999986,
%U 199999999999986,1999999999999986,19999999999999986,199999999999999986
%N 2*(10^n - 7).
%H Vincenzo Librandi, <a href="/A175237/b175237.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.: 6*x*(1 + 20*x)/((1-x)*(1-10*x)). - _Vincenzo Librandi_, Apr 26 2014
%t Join[{6},Table[FromDigits[Join[{1},PadLeft[{8,6},n,9]]],{n,2,20}]] (* _Harvey P. Dale_, Mar 22 2012 *)
%t CoefficientList[Series[6 (1 + 20 x)/((1 - x) (1 - 10 x)), {x, 0, 20}], x] (* _Vincenzo Librandi_, Apr 26 2014 *)
%o (Magma) [2*(10^n-7): n in [1..20]]; // _Vincenzo Librandi_, Apr 26 2014
%K nonn,easy
%O 1,1
%A _Vincenzo Librandi_, Nov 15 2010
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