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A218411 Numbers n for which sigma(n)/n = k+4/7 with integer k. 5
280, 18620, 411264, 804384, 871416, 1222144, 1284192, 164989440, 270138960, 318729600, 326781000, 396168192, 481572000, 623397600, 675347400, 995248800, 3444711424, 4426793280, 307030348800, 465036042240, 880719036120 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(19) > 10^11. - Donovan Johnson, Oct 31 2012

a(22) > 10^12. - Giovanni Resta, Nov 04 2012

LINKS

Table of n, a(n) for n=1..21.

FORMULA

sigma(n)/n = k+4/7 with integer k

CROSSREFS

Cf. A218428, A218409, A218410, A218412, A218413.

Sequence in context: A024214 A094895 A223107 * A272715 A282439 A255498

Adjacent sequences:  A218408 A218409 A218410 * A218412 A218413 A218414

KEYWORD

nonn

AUTHOR

Zdenek Cervenka, Oct 28 2012

EXTENSIONS

a(8)-a(18) from Donovan Johnson, Oct 31 2012

a(19)-a(21) from Giovanni Resta, Nov 04 2012

STATUS

approved

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Last modified February 27 03:50 EST 2020. Contains 332299 sequences. (Running on oeis4.)