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A219223 Numbers n such that (sigma(n)-n)/(tau(n)-1) is a perfect number. 0
30, 121, 252, 8432, 982081, 479499604, 1912369152, 2180771840 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
a(9) > 10^10. - Donovan Johnson, Nov 15 2012
LINKS
Table of n, a(n) for n=1..8.
FORMULA
Numbers n such that (sigma(n)-n)/(tau(n)-1) is a perfect number.
CROSSREFS
Sequence in context: A290391 A277451 A042764 * A042766 A042768 A122137
Adjacent sequences: A219220 A219221 A219222 * A219224 A219225 A219226
KEYWORD
nonn
AUTHOR
Zdenek Cervenka, Nov 15 2012
EXTENSIONS
a(6)-a(8) from Donovan Johnson, Nov 15 2012
STATUS
approved

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Last modified June 8 04:51 EDT 2024. Contains 373207 sequences. (Running on oeis4.)