The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A046685 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A046685

Numbers k such that the sum of cubes of divisors of k and the sum of 4th powers of divisors of k are relatively prime.
(history; published version)

#21 by Michael De Vlieger at Fri Aug 11 10:00:30 EDT 2023

STATUS

reviewed

approved

#20 by Michel Marcus at Fri Aug 11 01:45:41 EDT 2023

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proposed

reviewed

#19 by Michael De Vlieger at Thu Aug 10 21:00:29 EDT 2023

STATUS

editing

proposed

#18 by Michael De Vlieger at Thu Aug 10 21:00:27 EDT 2023

MATHEMATICA

Select[Range[25000], CoprimeQ[DivisorSigma[3, #], DivisorSigma[4, #]] &] (* Michael De Vlieger, Aug 10 2023 *)

STATUS

approved

editing

#17 by Susanna Cuyler at Sat May 08 22:57:24 EDT 2021

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reviewed

approved

#16 by Andrew Howroyd at Sat May 08 19:19:06 EDT 2021

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proposed

reviewed

#15 by Jon E. Schoenfield at Sat May 08 18:51:55 EDT 2021

STATUS

editing

proposed

#14 by Jon E. Schoenfield at Sat May 08 18:51:53 EDT 2021

NAME

Sum Numbers k such that the sum of cubes of divisors of n k and the sum of 4th powers of divisors of n k are relatively prime.

COMMENTS

It can be shown that this is a subset subsequence of A028982.

No term is divisible by a member term of A002476.

p^2 is a member term for every p in A003627. (End)

STATUS

approved

editing

#13 by N. J. A. Sloane at Tue Sep 24 09:20:36 EDT 2019

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proposed

approved

#12 by Michel Marcus at Tue Sep 24 04:40:26 EDT 2019

STATUS

editing

proposed