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A285109 a(n) = n multiplied by its smallest prime factor; a(1) = 1. 4
1, 4, 9, 8, 25, 12, 49, 16, 27, 20, 121, 24, 169, 28, 45, 32, 289, 36, 361, 40, 63, 44, 529, 48, 125, 52, 81, 56, 841, 60, 961, 64, 99, 68, 175, 72, 1369, 76, 117, 80, 1681, 84, 1849, 88, 135, 92, 2209, 96, 343, 100, 153, 104, 2809, 108, 275, 112, 171, 116, 3481, 120, 3721, 124, 189, 128, 325, 132, 4489, 136, 207 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..10000

FORMULA

a(n) = A020639(n) * n.

Other identities. For all n >= 1:

a(A285100(n)) = A065642(A285100(n)). [Agrees with A065642 on all terms of A285100, but not on any other points.]

PROG

(Scheme) (define (A285109 n) (* (A020639 n) n))

CROSSREFS

Cf. A005117, A020639, A032742, A253560, A285100.

Differs from A065642 for the first time at n=12. See A284342 for all the differing points.

Sequence in context: A121920 A318279 A065642 * A217579 A118585 A067666

Adjacent sequences:  A285106 A285107 A285108 * A285110 A285111 A285112

KEYWORD

nonn

AUTHOR

Antti Karttunen, Apr 19 2017

STATUS

approved

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Last modified March 19 23:02 EDT 2019. Contains 321343 sequences. (Running on oeis4.)