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A333986 Greatest prime factor of A007497(n). 0
2, 3, 2, 7, 2, 5, 3, 5, 7, 5, 7, 5, 127, 7, 8191, 5, 127, 13, 31, 127, 127, 89, 31, 17, 127, 31, 3221, 179, 151, 127, 8191, 13, 262657, 11939, 199, 257, 127, 127, 337, 257, 524287, 73, 1093, 547, 137, 241, 1093, 547, 331, 131071, 1093, 599479, 8191, 137, 127, 8191 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..56.

FORMULA

a(n) = A006530(A007497(n)). - Michel Marcus, Sep 09 2020

MATHEMATICA

f[1] = 2; f[n_] := f[n] = DivisorSigma[1, f[n - 1]]; Table[FactorInteger[f[n]][[-1, 1]], {n, 50}] (* Amiram Eldar, Sep 23 2020 *)

CROSSREFS

Cf. A006530, A007497.

Sequence in context: A104565 A144456 A262427 * A349664 A266258 A180916

Adjacent sequences:  A333983 A333984 A333985 * A333987 A333988 A333989

KEYWORD

nonn

AUTHOR

Richard Peterson, Sep 04 2020

EXTENSIONS

More terms from Michel Marcus, Sep 16 2020

STATUS

approved

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Last modified May 22 10:52 EDT 2022. Contains 353949 sequences. (Running on oeis4.)