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A050972 Smaller member of friendly pairs ordered by smallest maximal element. 10
6, 30, 80, 40, 12, 84, 66, 78, 102, 6, 28, 114, 240, 138, 120, 150, 174, 135, 186, 864, 222, 246, 60, 258, 282, 560, 318, 84, 270, 330, 84, 270, 1488, 354, 366, 720, 390, 402, 426, 360, 438, 880, 474, 498, 510, 440, 30, 140, 534, 132, 1040, 570, 582, 606 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Conjecture: If a(n) is in A005153, then A050973(n) is in A005153. It is natural to ask if there exists a generalization of the indicator function for A005153, call it m(n), such that m(n) = 1 for n in A005153, 0 < m(n) < 1 otherwise, and m(a(n)) <= m(A050973(n)) for all n. See also A017666. - Jaycob Coleman, Sep 27 2014

LINKS

Donovan Johnson, Table of n, a(n) for n = 1..10000

Eric Weisstein's World of Mathematics, Friendly Pair.

CROSSREFS

Cf. A050973 (larger member of pair), A074902 (friendly numbers).

Sequence in context: A305163 A038039 A258903 * A259918 A002444 A152788

Adjacent sequences:  A050969 A050970 A050971 * A050973 A050974 A050975

KEYWORD

nonn

AUTHOR

Eric W. Weisstein

STATUS

approved

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Last modified March 31 22:16 EDT 2020. Contains 333151 sequences. (Running on oeis4.)