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A119704
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a(n) = number of distinct prime factors of 10^n+1, omega(10^n+1).
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1
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1, 1, 1, 3, 2, 2, 2, 2, 2, 5, 3, 4, 3, 3, 4, 7, 5, 4, 3, 2, 4, 7, 4, 5, 3, 5, 3, 7, 4, 3, 7, 2, 4, 8, 4, 5, 6, 4, 3, 9, 4, 3, 7, 4, 4, 12, 4, 4, 9, 4, 7, 8, 4, 2, 6, 9, 5, 6, 5, 4, 6, 3, 3, 11, 3, 6, 8, 2, 4, 10, 11, 3, 5, 4, 7, 11, 6, 11, 7, 4, 9, 11, 3, 7, 8, 8, 3, 8, 4, 4, 11, 6, 4, 8, 4, 6, 8, 4
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,4
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LINKS
| M. Kamada, Factorizations of 100...001
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FORMULA
| a(n)=A104223(n-1), n>0. [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Aug 08 2008]
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EXAMPLE
| a(11) = 4 because 10^11+1 = 11*11*23*4093*8779: 4 distinct factors.
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MATHEMATICA
| Table[Length[FactorInteger[10^n + 1]], {n, 0, 50}] - Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), Jun 13 2006
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CROSSREFS
| Cf. A001221, A003021, A038371, A057934, A062397.
Sequence in context: A174550 A058758 A104223 * A057934 A122396 A037199
Adjacent sequences: A119701 A119702 A119703 * A119705 A119706 A119707
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KEYWORD
| nonn
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AUTHOR
| Lekraj Beedassy (blekraj(AT)yahoo.com), Jun 09 2006
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EXTENSIONS
| More terms from Don Reble (djr(AT)nk.ca), Jun 13 2006
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