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A047855 a(n)=T(7,n), array T given by A047848. 10
1, 2, 12, 112, 1112, 11112, 111112, 1111112, 11111112, 111111112, 1111111112, 11111111112, 111111111112, 1111111111112, 11111111111112, 111111111111112, 1111111111111112 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

COMMENTS

Range of A164898, apart from first term. [From Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Aug 30 2009]

FORMULA

(10^n + 8)/9. - Ralf Stephan, Feb 14 2004

a(0)=1, a(1)=2, a(n)=11*a(n-1)-10*a(n-2) for n>1. - Lambert Klasen (lambert.klasen(AT)gmx.net), Jan 28 2005

G.f.: (1-9x)/(1-11x+10x^2). [From Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Oct 05 2009]

a(n)=10*a(n-1)-8 (with a(0)=1) [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Aug 06 2010]

EXAMPLE

For n=1, a(1)=10*1-8=2; n=2, a(2)=10*2-8=12; n=3, a(3)=10*12-8=112 [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Aug 06 2010]

MAPLE

a[0]:=0:a[1]:=1:for n from 2 to 50 do a[n]:=10*a[n-1]+1 od: seq(a[n]+1, n=0..18); - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Mar 20 2008

PROG

(PARI) a(n)=if(n==0, 1, if(n==1, 2, 11*a(n-1)-10*a(n-2))) for(i=0, 10, print1(a(i), ", ")) (Klasen)

(Other) sage: [gaussian_binomial(n, 1, 10)+1 for n in xrange(0, 17)] # [From Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), May 29 2009]

CROSSREFS

n-th difference of a(n), a(n-1), ..., a(0) is 9^(n-1) for n=1, 2, 3, ...

Sequence in context: A158832 A102659 A191895 * A199045 A009232 A124213

Adjacent sequences:  A047852 A047853 A047854 * A047856 A047857 A047858

KEYWORD

nonn

AUTHOR

Clark Kimberling (ck6(AT)evansville.edu)

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Last modified February 15 18:47 EST 2012. Contains 205837 sequences.