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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
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.
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
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