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A073349 Numbers n such that sigma(n)/n is equal to sigma(k)/k for some k being superabundant (A004394). 0
1, 2, 4, 6, 12, 24, 28, 36, 48, 60, 120, 180, 234, 240, 360, 496, 600, 672, 720, 840, 1170, 1260, 1680, 1800, 2016, 2520, 4200, 5040, 8128, 10080, 12600, 15120, 22320, 25200, 27000, 27720, 37800, 55440, 55800, 55860, 110880, 138600, 166320, 167580, 277200 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Previous name was: Numbers n such that sigma(k)/k < sigma(n)/n for k=1,2,3...,n-1.

LINKS

Table of n, a(n) for n=1..45.

PROG

(PARI) lista(nn) = {vs = Set(); maxs = 0; for(n = 1, nn, news = sigma(n, -1); if (news > maxs, maxs = news; print1(n, ", "); vs = Set(concat(vs, maxs)); , if (setsearch(vs, news), print1(n, ", ")); ); ); } \\ Michel Marcus, Dec 02 2013

CROSSREFS

Cf. A004394.

Sequence in context: A217356 A030793 A085988 * A129301 A066523 A097212

Adjacent sequences:  A073346 A073347 A073348 * A073350 A073351 A073352

KEYWORD

easy,nonn

AUTHOR

Benoit Cloitre, Aug 23 2002

EXTENSIONS

New name and more terms from Michel Marcus, Dec 02 2013

STATUS

approved

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Last modified July 20 01:17 EDT 2019. Contains 325168 sequences. (Running on oeis4.)