The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A048741 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A048741

Product of aliquot divisors of composite n (1 and primes omitted).
(history; published version)

#12 by Michel Marcus at Sat Sep 07 08:49:25 EDT 2019

STATUS

reviewed

approved

#11 by Joerg Arndt at Sat Sep 07 08:14:17 EDT 2019

STATUS

proposed

reviewed

#10 by Michel Marcus at Sat Sep 07 05:16:05 EDT 2019

STATUS

editing

proposed

#9 by Michel Marcus at Sat Sep 07 05:15:41 EDT 2019

FORMULA

a(n) = A007956(A002808(n)). - Michel Marcus, Sep 07 2019

CROSSREFS

Cf. A002808, A007422, A007956, A048740.

STATUS

proposed

editing

#8 by Amiram Eldar at Sat Sep 07 05:10:11 EDT 2019

STATUS

editing

proposed

#7 by Amiram Eldar at Sat Sep 07 05:00:38 EDT 2019

MATHEMATICA

pd[n_] := n^(DivisorSigma[0, n]/2 - 1); pd /@ Select[Range[100], CompositeQ] (* Amiram Eldar, Sep 07 2019 *)

#6 by Amiram Eldar at Sat Sep 07 04:55:47 EDT 2019

LINKS

Amiram Eldar, <a href="/A048741/b048741.txt">Table of n, a(n) for n = 1..10000</a>

#5 by Amiram Eldar at Sat Sep 07 04:55:12 EDT 2019

DATA

2, 6, 8, 3, 10, 144, 14, 15, 64, 324, 400, 21, 22, 13824, 5, 26, 27, 784, 27000, 1024, 33, 34, 35, 279936, 38, 39, 64000, 74088, 1936, 2025, 46, 5308416, 7, 2500, 51, 2704, 157464, 55, 175616, 57, 58, 777600000, 62, 3969, 32768, 65, 287496, 4624, 69

EXTENSIONS

a(33) inserted by Amiram Eldar, Sep 07 2019

STATUS

approved

editing

#4 by Russ Cox at Sat Mar 31 10:32:38 EDT 2012

AUTHOR

Enoch Haga (Enokh(AT)comcast.net)

Enoch Haga

Discussion

Sat Mar 31

10:32

OEIS Server: https://oeis.org/edit/global/789

#3 by N. J. A. Sloane at Sun Feb 20 03:00:00 EST 2005

KEYWORD

easy,nonn,new

AUTHOR

Enoch Haga (Enokh(AT)aolcomcast.comnet)