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A342922 Numbers k such that A342925(k) = k + 2*A003415(k). 6
6, 28, 29, 496, 857, 1721, 8128, 164284, 6511664, 33550336 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Question: Are all odd terms in A001359?

Certainly any prime p such that A003415(p+1) = p + 2 satisfies the equation. See comments in A007850.

LINKS

Table of n, a(n) for n=1..10.

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]));

A342925(n) = A003415(sigma(n));

isA342922(n) = (A342925(n)==(n+(2*A003415(n))));

CROSSREFS

Cf. A000396 (subsequence), A001359, A007850, A203617, A342923, A342924, A342925.

Sequence in context: A215896 A211679 A261868 * A105402 A145551 A338125

Adjacent sequences:  A342919 A342920 A342921 * A342923 A342924 A342925

KEYWORD

nonn,more

AUTHOR

Antti Karttunen, Apr 07 2021

STATUS

approved

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Last modified January 24 09:42 EST 2022. Contains 350534 sequences. (Running on oeis4.)