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A098406
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a(n) = ((10^n)+17)/9.
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1
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3, 13, 113, 1113, 11113, 111113, 1111113, 11111113, 111111113, 1111111113, 11111111113, 111111111113, 1111111111113, 11111111111113, 111111111111113, 1111111111111113, 11111111111111113, 111111111111111113
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| A097683 gives numbers k such that a(k) is prime.
a(n) = A047855(n)+1 = A002275(n)+2.
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FORMULA
| a(1) = 3; a(n) = a(n-1)+10^(n-1).
a(1) = 3; a(n) = 10*a(n-1)-17.
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EXAMPLE
| a(5) = (100000+17)/9 = 11113.
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MATHEMATICA
| FromDigits/@Table[PadLeft[{3}, n, 1], {n, 20}] (* From Harvey P. Dale, June 18 2011 *)
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PROG
| (PARI) for(n=1, 18, print1(((10^n)+17)/9, ", "))
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CROSSREFS
| Cf. A097683, A047855, A002275.
Sequence in context: A181083 A090537 A063269 * A105431 A062447 A053583
Adjacent sequences: A098403 A098404 A098405 * A098407 A098408 A098409
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KEYWORD
| nonn,easy
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AUTHOR
| Klaus Brockhaus (klaus-brockhaus(AT)t-online.de), Sep 07 2004
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