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A086949
Numbers k such that reverse(k+9) = 5.
3
41, 491, 4991, 49991, 499991, 4999991, 49999991, 499999991, 4999999991, 49999999991, 499999999991, 4999999999991, 49999999999991, 499999999999991, 4999999999999991, 49999999999999991, 499999999999999991, 4999999999999999991, 49999999999999999991, 499999999999999999991
OFFSET
1,1
COMMENTS
reverse(a(n)) = A086946(n).
FORMULA
a(n) = 5*10^n - 9.
From Stefano Spezia, Dec 15 2022: (Start)
O.g.f.: x*(41 + 40*x)/((1 - x)*(1 - 10*x)).
E.g.f.: 4 - 9*exp(x) + 5*exp(10*x).
a(n) = 11*a(n-1) - 10*a(n-2) for n > 2. (End)
MATHEMATICA
5*10^Range[20]-9 (* Harvey P. Dale, Nov 29 2018 *)
PROG
(Magma) [5*10^n-9: n in [1..25] ]; // Vincenzo Librandi, Aug 22 2011
CROSSREFS
Sequence in context: A166843 A098958 A269073 * A177504 A297976 A208048
KEYWORD
nonn,base,easy
AUTHOR
Ray Chandler, Jul 24 2003
STATUS
approved