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A087025
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Sum of divisors of n-th cyclic number.
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2
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255360, 17205180696931968, 1951532915603927040, 12430490030984319840000, 9956179688423375044684800000, 6080633705911286890368486450696472902951229440, 4809378729404888733987843426081300724182624228548100710400
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| Calculated with Dario Alpern's ECM.
Extended using factors of 10^(A001913(n)-1)-1, see Kamada link.
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LINKS
| Ray Chandler, Table of n, a(n) for n = 1..42
Dario A. Alpern, Factorization using the Elliptic Curve Method.
Makoto Kamada, Factorizations of 11...11 (Repunit)
Eric Weisstein's World of Mathematics, Cyclic Number
Eric Weisstein's World of Mathematics, Divisor Function
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FORMULA
| a(n) = A000203(A004042(n+1)).
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CROSSREFS
| Cf. A001913, A087020-A087026.
Sequence in context: A034631 A168352 A147579 * A161534 A052197 A053076
Adjacent sequences: A087022 A087023 A087024 * A087026 A087027 A087028
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KEYWORD
| nonn
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AUTHOR
| Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Jul 30 2003
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EXTENSIONS
| a(12)-a(42) from Ray Chandler (rayjchandler(AT)sbcglobal.net), Nov 16 2011
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