The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A299153 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A299153

Numbers k such that sigma(k) and sigma(k^3) are both primes.
(history; published version)

#21 by Charles R Greathouse IV at Thu Sep 08 08:46:20 EDT 2022

PROG

(MAGMAMagma) [n: n in[1..10000000] | IsPrime(SumOfDivisors(n)) and IsPrime(SumOfDivisors(n^3))]

Discussion

Thu Sep 08

08:46

OEIS Server: https://oeis.org/edit/global/2944

#20 by Jon E. Schoenfield at Wed Sep 08 21:14:41 EDT 2021

STATUS

reviewed

approved

#19 by Michael De Vlieger at Wed Sep 08 21:06:06 EDT 2021

STATUS

proposed

reviewed

#18 by Jon E. Schoenfield at Wed Sep 08 20:59:44 EDT 2021

STATUS

editing

proposed

#17 by Jon E. Schoenfield at Wed Sep 08 20:59:42 EDT 2021

NAME

Numbers n k such that sigma(nk) and sigma(nk^3) are both primes.

STATUS

approved

editing

#16 by Alois P. Heinz at Tue Mar 13 18:08:58 EDT 2018

STATUS

proposed

approved

#15 by Chai Wah Wu at Tue Mar 13 18:04:59 EDT 2018

STATUS

editing

proposed

#14 by Chai Wah Wu at Tue Mar 13 18:04:47 EDT 2018

LINKS

Chai Wah Wu, <a href="/A299153/b299153.txt">Table of n, a(n) for n = 1..10203</a>

STATUS

approved

editing

#13 by Bruno Berselli at Tue Mar 13 13:09:58 EDT 2018

STATUS

reviewed

approved

#12 by Michel Marcus at Tue Mar 13 13:06:54 EDT 2018

STATUS

proposed

reviewed