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Revision History for A328393

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A328393

Numbers whose arithmetic derivative (A003415) is a squarefree number (A005117).
(history; published version)

#6 by Susanna Cuyler at Sat Oct 19 10:47:24 EDT 2019

STATUS

proposed

approved

#5 by Antti Karttunen at Sat Oct 19 09:12:16 EDT 2019

STATUS

editing

proposed

#4 by Antti Karttunen at Sat Oct 19 08:09:38 EDT 2019

LINKS

Antti Karttunen, <a href="/A328393/b328393.txt">Table of n, a(n) for n = 1..10000</a>

#3 by Antti Karttunen at Sat Oct 19 08:06:30 EDT 2019

COMMENTS

See A328234 for more comments.

CROSSREFS

Cf. A328252 (nonsquarefree terms), A157037, A192192, A327978 (other subsequences).

#2 by Antti Karttunen at Sat Oct 19 08:04:43 EDT 2019

NAME

allocated for Antti KarttunenNumbers whose arithmetic derivative (A003415) is a squarefree number (A005117).

DATA

2, 3, 5, 6, 7, 9, 10, 11, 13, 17, 18, 19, 21, 22, 23, 25, 26, 29, 30, 31, 33, 34, 37, 38, 41, 42, 43, 45, 47, 49, 53, 57, 58, 59, 61, 62, 63, 66, 67, 69, 70, 71, 73, 74, 75, 78, 79, 82, 83, 85, 89, 90, 93, 97, 98, 101, 102, 103, 105, 106, 107, 109, 110, 113, 114, 117, 118, 121, 126, 127, 129, 130, 131, 133, 134, 137, 139, 142

OFFSET

1,1

COMMENTS

See A328234 for more comments.

PROG

(PARI)

A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));

isA328393(n) = issquarefree(A003415(n));

CROSSREFS

Union of A000040 and A328234. Complement of A328303.

Cf. A005117, A008966, A003415.

KEYWORD

allocated

nonn

AUTHOR

Antti Karttunen, Oct 19 2019

STATUS

approved

editing

#1 by Antti Karttunen at Mon Oct 14 16:40:30 EDT 2019

NAME

allocated for Antti Karttunen

KEYWORD

allocated

STATUS

approved