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A110443 Index k of the least colossally abundant number c=A004490(k) with sigma(c)/c >= n. 1
2, 5, 9, 14, 19, 27, 40, 56, 82, 119, 180, 275, 426, 673, 1072, 1728, 2807, 4596, 7558, 12497, 20741, 34544, 57704, 96638, 162204, 272802, 459637, 775678, 1310959, 2218651, 3759507, 6377858 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

COMMENTS

For the numbers, instead of the indices, see A110442. The last term, a(33), yields a 48361012-digit number having 6375908 prime factors.

LINKS

Table of n, a(n) for n=2..33.

EXAMPLE

a(4)=9 because the 9th colossally abundant number is c=55440 and sigma(c)/c = 4.18701 > 4, while the 8th colossally abundant number is c'=5040 and sigma(c')/c' = 3.838 < 4.

CROSSREFS

Sequence in context: A025281 A160663 A024201 * A130029 A266450 A132296

Adjacent sequences:  A110440 A110441 A110442 * A110444 A110445 A110446

KEYWORD

nonn

AUTHOR

T. D. Noe, Jul 20 2005

EXTENSIONS

Definition and example clarified by Jonathan Sondow, Dec 08 2011

STATUS

approved

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Last modified January 17 23:15 EST 2019. Contains 319251 sequences. (Running on oeis4.)