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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
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
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: A360674 A324108 A324054 * A214409 A215509 A053480
KEYWORD
nonn
AUTHOR
Michel Marcus, Jul 22 2012
STATUS
approved