The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A344696 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A344696

a(n) = sigma(n) / gcd(sigma(n), A001615(n)).
(history; published version)

#15 by N. J. A. Sloane at Sat May 29 20:01:10 EDT 2021

STATUS

proposed

approved

#14 by Antti Karttunen at Sat May 29 08:11:19 EDT 2021

STATUS

editing

proposed

#13 by Antti Karttunen at Sat May 29 06:04:47 EDT 2021

COMMENTS

This is not multiplicative. The first point where a(m*n) = a(m)*a(n) does not hold for coprime m and n is 108 = 4*27, where a(108) = 35, although a(4) = 7 and a(27) = 10. See A344702.

LINKS

Antti Karttunen, <a href="/indexA344696/Si#SIGMANb344696.txt">Index entries Table of n, a(n) for sequences related to sigma(n) = 1..10404</a>

<a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>

CROSSREFS

Cf. A000203, A001615, A005117 (positions of ones), A344695, A344697, A344698, A344702.

#12 by Antti Karttunen at Sat May 29 06:02:24 EDT 2021

LINKS

Antti Karttunen, <a href="/A344696/a344696.txt">Data supplement: n, a(n) computed for n = 1..65537</a>

STATUS

approved

editing

#11 by Susanna Cuyler at Fri May 28 17:15:34 EDT 2021

STATUS

proposed

approved

#10 by Antti Karttunen at Fri May 28 15:33:48 EDT 2021

STATUS

editing

proposed

#9 by Antti Karttunen at Fri May 28 10:27:32 EDT 2021

CROSSREFS

Cf. also A344756.

#8 by Antti Karttunen at Fri May 28 10:09:40 EDT 2021

CROSSREFS

Cf. A000203, A001615, A005117 (positions of ones), A344695, A344697, A344698.

#7 by Antti Karttunen at Fri May 28 10:08:42 EDT 2021

CROSSREFS

Cf. A000203, A001615, A005117 (positions of ones), A344695, A344697.

#6 by Antti Karttunen at Thu May 27 14:44:07 EDT 2021

COMMENTS

This is not multiplicative. The first point where a(m*n) = a(m)*a(n) does not hold for coprime m and n is 108, = 4*27, where a(4*27) = a(108) = 35, although a(4) = 7 and a(27) = 10.