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A071189 Smallest prime factor of sum of divisors of n. 2
1, 3, 2, 7, 2, 2, 2, 3, 13, 2, 2, 2, 2, 2, 2, 31, 2, 3, 2, 2, 2, 2, 2, 2, 31, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 7, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 127, 2, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 2, 2, 11, 2, 2, 2, 2, 2, 2, 2 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

a(n) = A020639(A000203(n)).

MATHEMATICA

Table[FactorInteger[DivisorSigma[1, n]][[1, 1]], {n, 90}] (* From Harvey P. Dale, May 15 2011 *)

CROSSREFS

Cf. A071190, A071187.

Sequence in context: A010760 A085594 A085587 * A137822 A193574 A174238

Adjacent sequences:  A071186 A071187 A071188 * A071190 A071191 A071192

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), May 15 2002

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Last modified February 17 04:58 EST 2012. Contains 205985 sequences.