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A216826 Largest prime factor of the n-th primary pseudoperfect number A054377(n). 3
2, 3, 7, 43, 31, 47059, 3109, 1729101023519 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

See A054377 for comments, references, and links.

LINKS

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

EXAMPLE

42 = 2*3*7 is the third primary pseudoperfect number, so a(3) = 7.

CROSSREFS

Cf. A054377, A216825, A236433.

Sequence in context: A261564 A126263 A323605 * A030087 A106864 A282027

Adjacent sequences:  A216823 A216824 A216825 * A216827 A216828 A216829

KEYWORD

nonn,hard,more

AUTHOR

Jonathan Sondow, Sep 20 2012

STATUS

approved

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Last modified December 9 23:01 EST 2019. Contains 329880 sequences. (Running on oeis4.)