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A227769 First (n+1)-fold perfect number divided by first n-fold perfect number, or 0 if the quotient is not an integer. 5
6, 20, 252, 468996, 0, 0, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The first n-fold perfect numbers are A007539 = 1, 6, 120, 30240, 14182439040, 154345556085770649600, ...

For additional comments, references, links, and crossrefs, see A007539 and A227765.

LINKS

Table of n, a(n) for n=1..7.

FORMULA

a(n) = A007539(n+1)/A007539(n) if n < 5.

EXAMPLE

The first 4-fold and 5-fold perfect numbers are A007539(4) = 30240 and  A007539(5) = 14182439040, and 14182439040/30240 = 468996 is an integer, so a(4) = 468996.

CROSSREFS

Cf. A007539, A227765, A227766, A227767, A227768.

Sequence in context: A095854 A027268 A000388 * A267903 A280039 A216912

Adjacent sequences:  A227766 A227767 A227768 * A227770 A227771 A227772

KEYWORD

nonn

AUTHOR

Jonathan Sondow, Jul 30 2013

STATUS

approved

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Last modified February 21 18:45 EST 2019. Contains 320376 sequences. (Running on oeis4.)