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A161770
n 1's followed by three 0's.
1
1000, 11000, 111000, 1111000, 11111000, 111111000, 1111111000, 11111111000, 111111111000, 1111111111000, 11111111111000, 111111111111000, 1111111111111000, 11111111111111000, 111111111111111000, 1111111111111111000, 11111111111111111000, 111111111111111111000
OFFSET
1,1
COMMENTS
Sequence A159741 written in base 2.
FORMULA
a(n) = 1000*(10^n-1)/9 = 1000 * A002275(n).
G.f.: 1000*x/((10*x-1)*(x-1)).
MATHEMATICA
Table[FromDigits[PadLeft[{0, 0, 0}, n, 1]], {n, 4, 20}] (* Harvey P. Dale, Aug 07 2023 *)
CROSSREFS
Sequence in context: A017511 A326639 A017643 * A004632 A277397 A250449
KEYWORD
nonn,easy,base
AUTHOR
Jaroslav Krizek, Jun 18 2009
EXTENSIONS
Edited by Charles R Greathouse IV, Oct 12 2009
STATUS
approved