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A074592 Smallest prime factors of numbers that are not prime powers. 3
2, 2, 2, 2, 3, 2, 2, 3, 2, 2, 2, 2, 2, 3, 2, 5, 2, 2, 3, 2, 2, 2, 3, 2, 2, 2, 3, 2, 2, 5, 2, 3, 2, 2, 2, 3, 5, 2, 2, 3, 2, 2, 2, 3, 2, 7, 2, 2, 2, 2, 5, 2, 3, 2, 2, 7, 2, 3, 2, 5, 2, 2, 3, 2, 2, 2, 3, 2, 2, 2, 3, 2, 2, 5, 2, 3, 2, 7, 2, 2, 3, 2, 2, 3, 2, 2, 7, 2, 3, 2, 2, 2, 3, 2, 11, 2, 5, 2, 3, 2, 2, 2, 3, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(n)>2 iff n+1 and n+2 are prime powers (A006549).

LINKS

Table of n, a(n) for n=1..104.

FORMULA

a(n) = A020639(A024619(n)).

CROSSREFS

Cf. A074593, A074594, A074595.

Sequence in context: A327163 A324538 A305976 * A089993 A220431 A268317

Adjacent sequences:  A074589 A074590 A074591 * A074593 A074594 A074595

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Aug 25 2002

STATUS

approved

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Last modified December 7 03:27 EST 2019. Contains 329836 sequences. (Running on oeis4.)