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A082731 a(n) = smallest number k such that ms(k) - k = n, or 0 if no such number exists, where ms(k) = sum of divisors of k other than k. 2
6, 0, 20, 18, 12, 0, 8925, 196, 56, 0, 40, 0, 24, 0, 272, 0, 550, 100, 208, 36, 176, 0, 1312, 0, 112, 0, 80, 0, 48, 0, 945, 15376, 572, 0, 928, 0, 2205, 0, 5696, 162, 736, 1352, 9555, 0, 350, 0, 490, 0, 60, 0, 416, 72, 352, 0, 90, 0, 84, 0, 160, 968, 96, 0, 24704, 0, 108, 200 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

Caution: so far a(n)=0 only indicates no k<2*10^6 exists; non-existance is not proved. - R. J. Mathar, Jul 26 2007

LINKS

Table of n, a(n) for n=0..65.

MAPLE

A082731 := proc(n) local k; k := 1 ; while numtheory[sigma](k)-2*k <> n do k := k+1 ; if k = 2000000 then RETURN(0) ; fi ; od ; RETURN(k) ; end: seq(A082731(n), n=0..200) ; - R. J. Mathar, Jul 26 2007

CROSSREFS

Cf. A082730.

Sequence in context: A167298 A167356 A219540 * A167357 A064381 A062254

Adjacent sequences:  A082728 A082729 A082730 * A082732 A082733 A082734

KEYWORD

nonn

AUTHOR

Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Apr 14 2003

EXTENSIONS

More terms from R. J. Mathar, Jul 26 2007

STATUS

approved

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Last modified May 18 09:08 EDT 2013. Contains 225419 sequences.