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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 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.)