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A104890
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Number of distinct prime divisors of 66...661 (with n 6s).
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1
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1, 1, 1, 3, 2, 2, 2, 4, 1, 2, 3, 2, 3, 3, 2, 4, 1, 3, 2, 1, 1, 2, 4, 2, 3, 4, 1, 4, 4, 4, 3, 2, 4, 3, 3, 4, 3, 5, 3, 7, 2, 1, 3, 4, 3, 6, 3, 6, 4, 2
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,4
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COMMENTS
| Also number of distinct prime factors of 6/9*(10^(n + 1) - 1) - 5. - Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), Feb 26 2006
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EXAMPLE
| Number of distinct prime divisors of 61 is 1 (prime).
Number of distinct prime divisors of 661 is 1 (prime).
Number of distinct prime divisors of 6661 is 1 (prime).
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MATHEMATICA
| Table[Length[FactorInteger[6/9*(10^(n + 1) - 1) - 5]], {n, 1, 50}] - Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), Feb 26 2006
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CROSSREFS
| Cf. A104564.
Sequence in context: A163751 A067279 A096101 * A064123 A024703 A102845
Adjacent sequences: A104887 A104888 A104889 * A104891 A104892 A104893
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KEYWORD
| nonn
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AUTHOR
| Parthasarathy Nambi (PachaNambi(AT)yahoo.com), Apr 24 2005
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EXTENSIONS
| More terms from Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), Feb 26 2006
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