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A055559
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Primes of form 2999...999.
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0
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OFFSET
| 1,1
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COMMENTS
| a(8)=29999999999999999999999999999999999999999999999999999999 [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Aug 07 2010]
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FORMULA
| a(n)=3*10^n-1 and is prime
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EXAMPLE
| 3*10^n-1 is prime for {1,3,6,7,19,27,43,55,207} n gives how many digit 9 occurs in these numbers
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CROSSREFS
| Cf. A051200.
Sequence in context: A138755 A171720 A091751 * A144233 A125074 A033519
Adjacent sequences: A055556 A055557 A055558 * A055560 A055561 A055562
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KEYWORD
| base,nonn
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AUTHOR
| Labos E. (labos(AT)ana.sote.hu), Jul 10 2000
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