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A173811
a(n) = (8*10^n - 53)/9 for n > 0.
2
3, 83, 883, 8883, 88883, 888883, 8888883, 88888883, 888888883, 8888888883, 88888888883, 888888888883, 8888888888883, 88888888888883, 888888888888883, 8888888888888883, 88888888888888883, 888888888888888883, 8888888888888888883, 88888888888888888883, 888888888888888888883
OFFSET
1,1
FORMULA
a(n) = 10*a(n-1) + 53 for n > 0, a(0) = -5.
From Vincenzo Librandi, Jul 05 2012: (Start)
G.f.: x*(3+50*x)/((1-x)*(1-10*x)).
a(n) = 11*a(n-1) - 10*a(n-2). (End)
E.g.f.: exp(x)*(8*exp(9*x) - 53)/9. - Elmo R. Oliveira, Sep 09 2024
MATHEMATICA
NestList[10#+53&, 3, 20] (* Harvey P. Dale, Jun 13 2011 *)
CoefficientList[Series[(3+50*x)/((1-x)*(1-10*x)), {x, 0, 30}], x] (* Vincenzo Librandi, Jul 05 2012 *)
PROG
(Magma)[(8*10^n-53)/9: n in [1..20]]; // Vincenzo Librandi, Jul 05 2012
CROSSREFS
Cf. A093166.
Sequence in context: A020464 A036943 A178001 * A093166 A379603 A111648
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Feb 25 2010
STATUS
approved