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A139228 First differences of perfect numbers A000396. 11
22, 468, 7632, 33542208, 8556318720, 128848822272, 2305842870701260800, 2658455991569831742348849607813890048, 191561942608236104636337386514471893476304705594327040 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..9.

Philippe Ellia, On the distance between perfect numbers, 2012

F. Luca and C. Pomerance, On the radical of a perfect number, New York Journal of Math., 16 (2010), 23-30.

FORMULA

a(n) = A000396(n+1) - A000396(n).

EXAMPLE

a(1) = 22 because A000396(1) = 6 and A000396(2) = 28 then 28-6 = 22.

CROSSREFS

Cf. A000396, A139229, A139230, A139231, A139232, A139233, A139234, A139235, A139236, A139237.

Sequence in context: A170741 A218724 A276644 * A240782 A261135 A158535

Adjacent sequences:  A139225 A139226 A139227 * A139229 A139230 A139231

KEYWORD

nonn

AUTHOR

Omar E. Pol, Apr 18 2008

EXTENSIONS

More terms from Omar E. Pol, Oct 02 2012

STATUS

approved

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Last modified June 16 13:13 EDT 2019. Contains 324152 sequences. (Running on oeis4.)