A110443 Index k of the least colossally abundant number c=A004490(k) with sigma(c)/c >= n.

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

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 A361742

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