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A105694 10^n-10^(n-2). 0
1, 10, 99, 990, 9900, 99000, 990000, 9900000, 99000000, 990000000, 9900000000, 99000000000, 990000000000, 9900000000000, 99000000000000, 990000000000000, 9900000000000000, 99000000000000000, 990000000000000000 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

COMMENTS

Apply the Riordan array (1-x,x/(1+x)) to 11^n.

FORMULA

G.f.: (1-x^2)/(1-10x); a(0)=1, a(1)=10, a(n)=10^n-10^(n-2), n>1.

CROSSREFS

Sequence in context: A179556 A179477 A179555 * A179557 A000456 A138365

Adjacent sequences:  A105691 A105692 A105693 * A105695 A105696 A105697

KEYWORD

easy,nonn

AUTHOR

Paul Barry (pbarry(AT)wit.ie), Apr 17 2005

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Last modified February 17 02:48 EST 2012. Contains 205978 sequences.