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A028499 6-hyperperfect numbers: n = 6*(sigma(n)-n-1) + 1. 7
301, 16513, 60110701, 1977225901, 2733834545701 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(6) > 4*10^12. 232630479398401 is also a term. - Donovan Johnson, Nov 20 2012

LINKS

Table of n, a(n) for n=1..5.

J. S. McCranie, A study of hyperperfect numbers, J. Int. Seqs. Vol. 3 (2000) #P00.1.3

Eric Weisstein's World of Mathematics, Hyperperfect Number

CROSSREFS

Cf. A000396, A007593, A220290, A028500-A028502, A034916.

Sequence in context: A004226 A070192 A178267 * A145123 A068258 A075407

Adjacent sequences:  A028496 A028497 A028498 * A028500 A028501 A028502

KEYWORD

hard,more,nonn

AUTHOR

Jud McCranie

EXTENSIONS

a(5) from Donovan Johnson, Nov 20 2012

STATUS

approved

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Last modified December 21 08:26 EST 2014. Contains 252299 sequences.