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%I #16 Jun 29 2023 18:24:07
%S 12,192,1992,19992,199992,1999992,19999992,199999992,1999999992,
%T 19999999992,199999999992,1999999999992,19999999999992,
%U 199999999999992,1999999999999992,19999999999999992,199999999999999992
%N a(n) = k where R(k+8) = 2.
%C R(a(n)) = A086947(n).
%H Vincenzo Librandi, <a href="/A086948/b086948.txt">Table of n, a(n) for n = 1..300</a>
%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (11, -10).
%F a(n) = 2*(10^n - 4).
%F From _Chai Wah Wu_, Aug 01 2020: (Start)
%F a(n) = 11*a(n-1) - 10*a(n-2) for n > 2.
%F G.f.: x*(60*x + 12)/((x - 1)*(10*x - 1)). (End)
%t Table[10*FromDigits[PadRight[{1},n,9]]+2,{n,20}] (* _Harvey P. Dale_, Dec 15 2017 *)
%o (Magma) [2*(10^n-4): n in [1..25] ]; // _Vincenzo Librandi_, Aug 22 2011
%Y Cf. A085331.
%K nonn,easy
%O 1,1
%A _Ray Chandler_, Jul 24 2003
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