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A214413 a(n) is the smallest m such that the irreducible fraction m/n is not an abundancy outlaw. 2
1, 3, 4, 7, 6, 13, 8, 15, 13, 19, 12, 29, 14, 25, 26, 31, 18, 41, 20, 47, 32, 37, 24, 65, 31, 43, 40, 57, 30, 73, 32, 63, 50, 55, 48, 91, 38, 61, 56, 93, 42, 97, 44, 85, 82, 73, 48, 125, 57, 93, 74, 99, 54, 121, 72, 125, 80, 91, 60, 169, 62, 97, 104, 127, 84 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

The theorem on page 7 of Stanton and Holdener gives conditions for a rational to be an abundancy outlaw.

For a given n, these conditions have been checked by starting with m/n=sigma(n)/n and then increasing m until they fail.

LINKS

Michel Marcus, Table of n, a(n) for n = 1..1000

William G. Stanton and Judy A. Holdener, Abundancy "Outlaws" of the Form (sigma(N) + t)/N, Journal of Integer Sequences , Vol 10 (2007) , Article 07.9.6.

EXAMPLE

a(3) = 4 because 4/3 is the abundancy index of 3, so 4/3 is not an abundancy outlaw.

CROSSREFS

Smaller than or equal to A214409.

Sequence in context: A003981 A324108 A324054 * A214409 A215509 A053480

Adjacent sequences:  A214410 A214411 A214412 * A214414 A214415 A214416

KEYWORD

nonn

AUTHOR

Michel Marcus, Jul 22 2012

STATUS

approved

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Last modified January 23 16:48 EST 2020. Contains 331173 sequences. (Running on oeis4.)