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A258567 Smallest prime factors of 2-full numbers. 6
1, 2, 2, 3, 2, 5, 3, 2, 2, 7, 2, 2, 3, 2, 2, 11, 5, 2, 2, 13, 2, 2, 2, 3, 3, 2, 2, 17, 2, 7, 19, 2, 2, 2, 3, 2, 2, 2, 23, 2, 5, 2, 3, 2, 3, 2, 2, 29, 2, 2, 31, 2, 2, 2, 2, 3, 3, 2, 2, 5, 2, 3, 11, 2, 37, 2, 2, 3, 2, 2, 41, 2, 2, 2, 43, 2, 2, 2, 3, 2, 2, 3 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(n) = A020639(A001694(n));

a(A258599(n)) = A000040(n) and a(m) != A000040(n) for m < A258599(n).

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

PROG

(Haskell)

a258567 = a020639 . a001694

CROSSREFS

Cf. A001694, A020639, A258599, A258568, A258569, A258570, A258571.

Sequence in context: A304716 A237984 A118136 * A076396 A076397 A254269

Adjacent sequences:  A258564 A258565 A258566 * A258568 A258569 A258570

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Jun 06 2015

STATUS

approved

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Last modified December 7 22:22 EST 2021. Contains 349589 sequences. (Running on oeis4.)