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A147816 Concatenation of n digits 1 and 2(n-1) digits 0. 2
1, 1100, 1110000, 1111000000, 1111100000000, 1111110000000000, 1111111000000000000, 1111111100000000000000, 1111111110000000000000000, 1111111111000000000000000000, 1111111111100000000000000000000 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(n) is also A016152(n) written in base 2.

LINKS

Table of n, a(n) for n=1..11.

Index entries for linear recurrences with constant coefficients, signature (1100,-100000).

FORMULA

a(n) = A138119(n)/10.

a(n) = [(10^n-1)*10^(2*n-2)]/9, with n>=1. [From Paolo P. Lava, Nov 26 2008]

a(n) = 1100*a(n-1)-100000*a(n-2). G.f.: x / ((100*x-1)*(1000*x-1)). - Colin Barker, Sep 16 2013

EXAMPLE

n ...... a(n)

1 ....... 1

2 ...... 1100

3 ..... 1110000

4 .... 1111000000

5 ... 1111100000000

PROG

(PARI) Vec(x/((100*x-1)*(1000*x-1))  + O(x^100)) \\ Colin Barker, Sep 16 2013

CROSSREFS

Cf. A000533, A016152, A135577, A138119, A138120, A138144, A138145, A138146, A138721, A138826, A147757, A147759.

Sequence in context: A281039 A078199 A271472 * A050926 A083933 A080317

Adjacent sequences:  A147813 A147814 A147815 * A147817 A147818 A147819

KEYWORD

base,easy,nonn

AUTHOR

Omar E. Pol, Nov 13 2008

STATUS

approved

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Last modified October 20 04:37 EDT 2018. Contains 316378 sequences. (Running on oeis4.)