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A087021
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Number of distinct prime factors of n-th cyclic number.
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8
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4, 8, 9, 8, 10, 8, 10, 21, 23, 19, 19, 15, 16, 12, 11, 33, 31, 19, 24, 22, 24, 18, 14, 33, 39, 23, 36, 13, 13, 19, 36, 32, 29, 27, 25, 11, 20, 56, 37, 46, 25, 22, 21, 16, 47, 25, 33, 22, 55, 32, 25
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OFFSET
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1,1
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COMMENTS
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A004042(n) factorized with Dario Alpern's ECM.
Extended using factors of 10^(A001913(n)-1)-1, see Kamada link.
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LINKS
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FORMULA
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EXAMPLE
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A004042(2) = 142857 = 37*13*11*3^3, therefore a(1) =
#{3,11,13,37} = 4.
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CROSSREFS
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KEYWORD
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nonn,more,hard
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AUTHOR
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EXTENSIONS
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a(3) corrected, a(12)-a(42) added by Ray Chandler, Nov 16 2011
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STATUS
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approved
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