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 A087026 Euler's totient of n-th cyclic number. 7
 77760, 1382399778816000, 98221093640386560, 1053590173895849103360, 821095240766161265049600000, 511883170649353472639948811682935064652736000, 410719109641406326635474611575828305116907342385175347200 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Calculated with Dario Alpern's ECM. Extended using factors of 10^(A001913(n)-1)-1, see Kamada link. LINKS Max Alekseyev, Table of n, a(n) for n = 1..51 (first 42 terms from Ray Chandler) Dario A. Alpern, Factorization using the Elliptic Curve Method. Makoto Kamada, Factorizations of 11...11 (Repunit) Eric Weisstein's World of Mathematics, CyclicNumber Eric Weisstein's World of Mathematics, Totient Function FORMULA a(n) = A000010(A004042(n+1)). CROSSREFS Cf. A001913, A087020, A087021, A087022, A087023, A087024, A087025. Sequence in context: A069044 A250012 A235979 * A133971 A133973 A133974 Adjacent sequences:  A087023 A087024 A087025 * A087027 A087028 A087029 KEYWORD nonn AUTHOR Reinhard Zumkeller, Jul 30 2003 EXTENSIONS a(12)-a(42) from Ray Chandler, Nov 16 2011 STATUS approved

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Last modified July 7 12:47 EDT 2022. Contains 355148 sequences. (Running on oeis4.)