A173812 a(n) = (8*10^n - 17)/9 for n > 0.

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Offset: 1

Author

Vincenzo Librandi, Feb 25 2010

Keywords

• nonn
• easy

Links

• Vincenzo Librandi, Table of n, a(n) for n = 1..100
• Index entries for linear recurrences with constant coefficients, signature (11,-10).

Crossrefs

Cf. A093171.

Programs

Magma

[(8*10^n-17)/9: n in [1..20]]; // Vincenzo Librandi, Jul 05 2012

Mathematica

CoefficientList[Series[(7+10*x)/((1-x)*(1-10*x)),{x,0,30}],x] (* Vincenzo Librandi, Jul 05 2012 *)
Table[FromDigits[PadLeft[{7},n,8]],{n,20}] (* Harvey P. Dale, Jun 22 2013 *)

Formula

a(n) = 10*a(n-1) + 17 with n > 0, a(0)=-1.

From Vincenzo Librandi, Jul 05 2012: (Start)

a(n) = 11*a(n-1) - 10*a(n-2) for n > 2.

G.f.: x*(7+10*x)/((1-x)*(1-10*x)). (End)

E.g.f.: 1 + exp(x)*(8*exp(9*x) - 17)/9. - Elmo R. Oliveira, Sep 09 2024