The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A336928 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A336928

a(n) = A329697(sigma(n)), where A329697 is totally additive with a(2) = 0 and a(p) = 1 + a(p-1) for odd primes.
(history; published version)

#8 by Susanna Cuyler at Tue Aug 11 10:38:28 EDT 2020

STATUS

proposed

approved

#7 by Antti Karttunen at Tue Aug 11 10:15:38 EDT 2020

STATUS

editing

proposed

#6 by Antti Karttunen at Tue Aug 11 01:14:30 EDT 2020

CROSSREFS

Cf. also A336469, A336694, A336927, A336929.

#5 by Antti Karttunen at Tue Aug 11 01:09:41 EDT 2020

NAME

a(n) = A329697(sigma(n)), where A329697 is totally additive with a(2) = 0 and a(p) = 1 + a(p-1) for odd primes.

#4 by Antti Karttunen at Tue Aug 11 01:06:15 EDT 2020

FORMULA

Additive with a(p^e) = A329697(sigma(p^e)) = A329697(1+ p + p^2 + ... + p^e).

#3 by Antti Karttunen at Tue Aug 11 01:01:04 EDT 2020

LINKS

Antti Karttunen, <a href="/A336928/b336928.txt">Table of n, a(n) for n = 1..65537</a>

#2 by Antti Karttunen at Tue Aug 11 00:50:11 EDT 2020

NAME

allocated for Antti Karttunen

a(n) = A329697(sigma(n)).

DATA

0, 1, 0, 2, 1, 1, 0, 2, 2, 2, 1, 2, 2, 1, 1, 3, 2, 3, 1, 3, 0, 2, 1, 2, 3, 3, 1, 2, 2, 2, 0, 4, 1, 3, 1, 4, 3, 2, 2, 3, 3, 1, 2, 3, 3, 2, 1, 3, 4, 4, 2, 4, 3, 2, 2, 2, 1, 3, 2, 3, 3, 1, 2, 5, 3, 2, 1, 4, 1, 2, 2, 4, 3, 4, 3, 3, 1, 3, 1, 4, 4, 4, 3, 2, 3, 3, 2, 3, 3, 4, 2, 3, 0, 2, 2, 4, 4, 5, 3, 5, 2, 3, 2, 4, 1

OFFSET

1,4

LINKS

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

FORMULA

Additive with a(p^e) =

a(n) = A329697(A000203(n)).

PROG

(PARI)

A329697(n) = { my(f=factor(n)); sum(k=1, #f~, if(2==f[k, 1], 0, f[k, 2]*(1+A329697(f[k, 1]-1)))); };

A336928(n) = A329697(sigma(n));

CROSSREFS

Cf. A000203, A329697.

Cf. also A336694, A336927, A336929.

KEYWORD

allocated

nonn

AUTHOR

Antti Karttunen, Aug 11 2020

STATUS

approved

editing

#1 by Antti Karttunen at Sat Aug 08 02:41:11 EDT 2020

NAME

allocated for Antti Karttunen

KEYWORD

allocated

STATUS

approved