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A087026
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Euler's totient of n-th cyclic number.
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7
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77760, 1382399778816000, 98221093640386560, 1053590173895849103360, 821095240766161265049600000, 511883170649353472639948811682935064652736000, 410719109641406326635474611575828305116907342385175347200
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OFFSET
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1,1
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COMMENTS
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Calculated 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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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
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FORMULA
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a(n) = A000010(A004042(n+1)).
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CROSSREFS
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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
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KEYWORD
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nonn
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AUTHOR
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Reinhard Zumkeller, Jul 30 2003
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EXTENSIONS
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a(12)-a(42) from Ray Chandler, Nov 16 2011
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STATUS
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approved
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