cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A103456 a(n) = 0^n + 10^n - 1.

Original entry on oeis.org

1, 9, 99, 999, 9999, 99999, 999999, 9999999, 99999999, 999999999, 9999999999, 99999999999, 999999999999, 9999999999999, 99999999999999, 999999999999999, 9999999999999999, 99999999999999999, 999999999999999999
Offset: 0

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Author

Paul Barry, Feb 06 2005

Keywords

Comments

A transform of 10^n under the matrix A103452.
Except for n = 0, the same as A002283. - Felix Fröhlich, Jun 22 2021

Crossrefs

Programs

  • Magma
    [1] cat [10^n -1: n in [1..40]]; // G. C. Greubel, Jun 21 2021
    
  • Mathematica
    Table[Boole[n==0] + 10^n -1, {n,0,40}] (* Alonso del Arte, Nov 03 2019 *)
  • PARI
    a(n) = 0^n + 10^n - 1 \\ Felix Fröhlich, Jun 22 2021
    
  • PARI
    Vec((1 - 2*x + 10*x^2)/((1 - x)*(1 - 10*x)) + O(x^20)) \\ Felix Fröhlich, Jun 22 2021
  • Sage
    [1]+[10^n -1 for n in (1..40)] # G. C. Greubel, Jun 21 2021
    

Formula

G.f.: (1 - 2*x + 10*x^2)/((1 - x)*(1 - 10*x));
a(n) = Sum_{k = 0..n} A103452(n, k)*10^k;
a(n) = Sum_{k = 0..n} (2*0^(n-k) - 1)*0^(k*(n-k))*10^k.
a(n) = A002283(n), n > 0. - R. J. Mathar, Aug 30 2008
E.g.f.: 1 - exp(x) + exp(10*x). - G. C. Greubel, Jun 21 2021