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A212611 Primitive deficient numbers n having a companion m > n such that sigma(n)/n = sigma(m)/m (ordered by increasing (smallest possible) m). 2
135, 3375, 25137, 68607, 22113, 557375, 451737, 1278316, 273, 6739509, 188325, 8775, 9020375, 20365625, 1083537, 3416875, 17875, 1995, 171387125, 382536063, 49166, 366776, 1487640245, 417725 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

These numbers n = a(k) are listed in the order of increasing companions m = A212612(k). All these numbers appear to have only one companion.

LINKS

Table of n, a(n) for n=1..24.

FORMULA

a(n) = A212610(2n-1). - M. F. Hasler, Feb 22 2013

CROSSREFS

Cf. A211680 (pairs of deficient numbers).

Cf. A212610 (pairs of primitive deficient numbers).

Sequence in context: A195671 A332428 A212608 * A004005 A248009 A143404

Adjacent sequences:  A212608 A212609 A212610 * A212612 A212613 A212614

KEYWORD

nonn,more

AUTHOR

T. D. Noe, May 23 2012

EXTENSIONS

a(10)-a(18) from Donovan Johnson, May 24 2012

a(19)-a(24) from Donovan Johnson, Jun 06 2012

STATUS

approved

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Last modified June 30 02:41 EDT 2022. Contains 354913 sequences. (Running on oeis4.)