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A086948
a(n) = k where R(k+8) = 2.
2
12, 192, 1992, 19992, 199992, 1999992, 19999992, 199999992, 1999999992, 19999999992, 199999999992, 1999999999992, 19999999999992, 199999999999992, 1999999999999992, 19999999999999992, 199999999999999992
OFFSET
1,1
COMMENTS
R(a(n)) = A086947(n).
FORMULA
a(n) = 2*(10^n - 4).
From Chai Wah Wu, Aug 01 2020: (Start)
a(n) = 11*a(n-1) - 10*a(n-2) for n > 2.
G.f.: x*(60*x + 12)/((x - 1)*(10*x - 1)). (End)
MATHEMATICA
Table[10*FromDigits[PadRight[{1}, n, 9]]+2, {n, 20}] (* Harvey P. Dale, Dec 15 2017 *)
PROG
(Magma) [2*(10^n-4): n in [1..25] ]; // Vincenzo Librandi, Aug 22 2011
CROSSREFS
Cf. A085331.
Sequence in context: A230757 A196483 A196716 * A230539 A230750 A358367
KEYWORD
nonn,easy
AUTHOR
Ray Chandler, Jul 24 2003
STATUS
approved