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A173193 (2*10^n+43)/9. 1
7, 27, 227, 2227, 22227, 222227, 2222227, 22222227, 222222227, 2222222227, 22222222227, 222222222227, 2222222222227, 22222222222227, 222222222222227, 2222222222222227, 22222222222222227, 222222222222222227 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

n-1 2's followed by a 7.

LINKS

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

Markus Tervooren, Factorizations of (2)w7

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

FORMULA

a(n) = 10*a(n-1)-43 with n>1, a(1)=7. [Vincenzo Librandi, Dec 05 2010]

a(n) = a(n-1)+2*10^(n-1) with n>1, a(1)=7. [Zak Seidov, Dec 05 2010]

a(n) = 11*a(n-1)-10*a(n-2). G.f.: -x*(50*x-7)/((x-1)*(10*x-1)). [Colin Barker, Jan 24 2013]

CROSSREFS

Sequence in context: A192250 A035081 A193257 * A196323 A003148 A033910

Adjacent sequences:  A173190 A173191 A173192 * A173194 A173195 A173196

KEYWORD

easy,nonn

AUTHOR

Ivan Panchenko, Feb 12 2010

EXTENSIONS

More terms from Vincenzo Librandi, Feb 24 2010

STATUS

approved

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Last modified December 14 17:44 EST 2019. Contains 329979 sequences. (Running on oeis4.)