A173262 - OEIS

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A173262

a(n) = (2*10^n+61)/9

9, 29, 229, 2229, 22229, 222229, 2222229, 22222229, 222222229, 2222222229, 22222222229, 222222222229, 2222222222229, 22222222222229, 222222222222229, 2222222222222229, 22222222222222229, 222222222222222229

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OFFSET

1,1

COMMENTS

n-1 2's followed by a 9.

LINKS

Table of n, a(n) for n=1..18.

Markus Tervooren, Factorizations of (2)w9

Index entries for linear recurrences with constant coefficients, signature (11, -10).

FORMULA

a(n)= 11*a(n-1) -10*a(n-2). G.f.: x*(-9+70*x)/((10*x-1)*(1-x)). [From R. J. Mathar, Feb 21 2010]

a(n)=10*a(n-1)-61, (with a(1)=9) [From Vincenzo Librandi, Feb 24 2010]