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A087024 Number of divisors of n-th cyclic number. 5
32, 384, 1280, 576, 1536, 384, 1536, 4194304, 16777216, 3538944, 1769472, 110592, 221184, 13824, 6912, 48318382080, 9663676416, 3538944, 75497472, 14155776, 56623104, 884736, 55296, 57982058496, 3710851743744, 37748736, 695784701952, 27648, 27648, 2654208 (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, Cyclic Number
Eric Weisstein's World of Mathematics, Divisor Function
FORMULA
a(n) = A000005(A004042(n+1)).
CROSSREFS
Cf. A001913, A087020, A087021, A087022, A087023, A087025, A087026.
Sequence in context: A300935 A300879 A301489 * A128798 A086942 A247995
Adjacent sequences: A087021 A087022 A087023 * A087025 A087026 A087027
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 19 00:30 EDT 2024. Contains 374388 sequences. (Running on oeis4.)