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A138118
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Concatenation of 2n-1 digits 1 and n digits 0.
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10
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10, 11100, 11111000, 11111110000, 11111111100000, 11111111111000000, 11111111111110000000, 11111111111111100000000, 11111111111111111000000000, 11111111111111111110000000000
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OFFSET
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1,1
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COMMENTS
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LINKS
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FORMULA
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O.g.f.: 10*(1+100x)/[(-1+1000x)*(-1+10x)]. a(n)=A100706(n)*10^n = 10*a(n-1)+11*1000^n. - R. J. Mathar, Apr 03 2008
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EXAMPLE
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n .......... a(n)
1 ........... 10
2 ......... 11100
3 ....... 11111000
4 ..... 11111110000
5 ... 11111111100000
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MATHEMATICA
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FromDigits/@Table[Join[PadRight[{}, 2n-1, 1], PadRight[{}, n, 0]], {n, 15}] (* Harvey P. Dale, Dec 09 2011 *)
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CROSSREFS
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KEYWORD
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easy,nonn,base
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AUTHOR
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STATUS
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approved
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