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A098611 a(n) = 10^n-(-1)^n. 3
0, 11, 99, 1001, 9999, 100001, 999999, 10000001, 99999999, 1000000001, 9999999999, 100000000001, 999999999999, 10000000000001, 99999999999999, 1000000000000001, 9999999999999999, 100000000000000001, 999999999999999999, 10000000000000000001 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,2
LINKS
FORMULA
a(n) = A098610(n)-2*(-1)^n = A098609(n) / A098610(n).
From Wesley Ivan Hurt, Apr 05 2015: (Start)
G.f.: 11*x/(1-9*x-10*x^2).
a(n) = 9*a(n-1) + 10*a(n-2). (End)
MAPLE
A098611:=n->10^n-(-1)^n: seq(A098611(n), n=0..30); # Wesley Ivan Hurt, Apr 05 2015
MATHEMATICA
Table[(10^n - (-1)^n), {n, 0, 30}] (* or *)
CoefficientList[Series[11 x/(1 - 9 x - 10 x^2), {x, 0, 30}], x] (* Wesley Ivan Hurt, Apr 05 2015 *)
LinearRecurrence[{9, 10}, {0, 11}, 20] (* Vincenzo Librandi, Apr 06 2015 *)
PROG
(Magma) [10^n-(-1)^n : n in [0..30]]; // Wesley Ivan Hurt, Apr 05 2015
(PARI) vector(20, n, 10^(n-1)+(-1)^n) \\ Derek Orr, Apr 05 2015
CROSSREFS
Sequence in context: A190870 A037510 A037693 * A090337 A287196 A288362
KEYWORD
easy,nonn
AUTHOR
Henry Bottomley, Sep 17 2004
STATUS
approved

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Last modified March 28 13:25 EDT 2024. Contains 371254 sequences. (Running on oeis4.)