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Revision History for A358215

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Showing entries 1-10 | older changes

A358215

Numbers k for which there is no prime p such that p^p divides the arithmetic derivative of k, A003415(k).
(history; published version)

#21 by OEIS Server at Thu Feb 22 20:08:24 EST 2024

LINKS

Antti Karttunen, <a href="/A358215/b358215_1.txt">Table of n, a(n) for n = 1..10000</a>

#20 by N. J. A. Sloane at Thu Feb 22 20:08:24 EST 2024

STATUS

proposed

approved

Discussion

Thu Feb 22

20:08

OEIS Server: Installed first b-file as b358215.txt.

#19 by Antti Karttunen at Thu Feb 22 20:04:51 EST 2024

STATUS

editing

proposed

#18 by Antti Karttunen at Thu Feb 22 06:23:06 EST 2024

PROG

(PARI)

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

isA048103(n) = { my(f=factor(n)); for(i=1, #f~, if (f[i, 1] <= f[i, 2], return(0))); return(1); }; \\ From A048103.

isA358215(n) = isA048103(A003415(n));

CROSSREFS

Cf. A003415, A327934, A351088, A359550, A368915 (characteristic function).

#17 by Antti Karttunen at Thu Feb 22 06:22:22 EST 2024

PROG

(PARI)

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

A359550(n) = { my(f = factor(n)); prod(k=1, #f~, (f[k, 2]<f[k, 1])); };

A368915(n) = ((n>1)&&A359550(A003415(n)));

isA358215(n) = A368915(n);

#16 by Antti Karttunen at Thu Feb 22 06:21:38 EST 2024

LINKS

Antti Karttunen, <a href="/A358215/b358215_1.txt">Table of n, a(n) for n = 1..10000</a>

#15 by Antti Karttunen at Thu Feb 22 06:14:27 EST 2024

CROSSREFS

Subsequence of A048103.

Cf. A003415, A048103, A327934, A351088, A368915 (characteristic function).

#14 by Antti Karttunen at Wed Feb 14 05:38:07 EST 2024

CROSSREFS

Cf. A003415, A048103, A327934, A351088, A368915 (characteristic function).

STATUS

approved

editing

Discussion

Wed Feb 21

11:32

OEIS Server: This sequence has not been edited or commented on for a week
yet is not proposed for review.  If it is ready for review, please
visit https://oeis.org/draft/A358215 and click the button that reads
"These changes are ready for review by an OEIS Editor."

Thanks.
  - The OEIS Server

#13 by Michel Marcus at Sun Jan 14 17:31:34 EST 2024

STATUS

reviewed

approved

#12 by Andrew Howroyd at Sun Jan 14 16:36:33 EST 2024

STATUS

proposed

reviewed