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A078552 Largest prime dividing sigma(3,n). 1
3, 7, 73, 7, 7, 43, 13, 757, 7, 37, 73, 157, 43, 7, 151, 13, 757, 7, 73, 43, 37, 13, 13, 829, 157, 73, 73, 271, 7, 19, 73, 37, 13, 43, 757, 43, 7, 157, 13, 547, 43, 139, 73, 757, 13, 103, 151, 1063, 829, 13, 157, 919, 73, 37, 43, 7, 271, 163, 73, 523, 19, 757, 337, 157 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

LINKS

Amiram Eldar, Table of n, a(n) for n = 2..10000

FORMULA

a(n) = A006530(A001158(n)).

MATHEMATICA

gpf[n_] := FactorInteger[n][[-1, 1]]; a[n_] := gpf[DivisorSigma[3, n]]; Array[a, 65, 2] (* Amiram Eldar, Aug 01 2019 *)

CROSSREFS

Cf. A006530, A001157-A001160, A071190.

Sequence in context: A094008 A209477 A209336 * A091259 A354891 A354893

Adjacent sequences:  A078549 A078550 A078551 * A078553 A078554 A078555

KEYWORD

nonn

AUTHOR

Labos Elemer, Dec 05 2002

STATUS

approved

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Last modified July 1 02:58 EDT 2022. Contains 354947 sequences. (Running on oeis4.)