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 A087022 Total number of prime factors of n-th cyclic number. 0
 6, 9, 12, 10, 11, 9, 11, 23, 25, 25, 22, 18, 19, 15, 14, 38, 35, 24, 28, 25, 27, 21, 17, 38, 44, 27, 43, 16, 16, 23, 42, 35, 37, 30, 29, 14, 23, 62, 41, 51, 28, 26 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS A004042(n) factorized with Dario Alpern's ECM. Extended using factors of 10^(A001913(n)-1)-1, see Kamada link. LINKS Dario A. Alpern, Factorization using the Elliptic Curve Method. Makoto Kamada, Factorizations of 11...11 (Repunit) Eric Weisstein's World of Mathematics, Cyclic Number FORMULA a(n) = A001222(A004042(n+1)). EXAMPLE A004042(2) = 142857 = 37*13*11*3^3, therefore a(1) = A087021(1)+2 = 6. CROSSREFS Cf. A001913, A087020-A087026. Sequence in context: A125971 A322158 A143710 * A315951 A081392 A225868 Adjacent sequences:  A087019 A087020 A087021 * A087023 A087024 A087025 KEYWORD nonn,more,hard AUTHOR Reinhard Zumkeller, Jul 30 2003 EXTENSIONS a(3) corrected, a(12)-a(42) added by Ray Chandler, Nov 16 2011 STATUS approved

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Last modified May 20 12:33 EDT 2019. Contains 323422 sequences. (Running on oeis4.)