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A345002 Numbers k such that A345001(k)/A342001(k) is a positive natural number and a divisor of k. 2
6, 28, 171, 496, 8128, 478800, 32317272, 33550336 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..8.

Index entries for sequences where odd perfect numbers must occur, if they exist at all

PROG

(PARI)

A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));

A003557(n) = (n/factorback(factorint(n)[, 1]));

isA345002(n) = if(1==n, 0, my(d=A003415(n), s=sigma(n)+d-(n+n), r=s/(d/A003557(n))); (r>0&&1==denominator(r)&&!(n%r)));

CROSSREFS

Cf. A000396 (subsequence), A003415, A003557, A342001, A345001.

Cf. also A344755.

Sequence in context: A173081 A278015 A338810 * A169723 A052395 A034660

Adjacent sequences:  A344999 A345000 A345001 * A345003 A345004 A345005

KEYWORD

nonn,more

AUTHOR

Antti Karttunen, Jun 05 2021

STATUS

approved

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Last modified May 23 04:06 EDT 2022. Contains 353959 sequences. (Running on oeis4.)