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A089748 Numbers n such that n divides (sum of proper divisors of n + product of proper divisors of n). 0
2, 6, 28, 120, 496, 672, 8128, 30240, 32760, 523776 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

All perfect numbers belong to this sequence.

Every term of A007691 is in this sequence. - T. D. Noe, Sep 29 2005

LINKS

Table of n, a(n) for n=1..10.

MATHEMATICA

l = {}; Do[d = Drop[Divisors[n], -1]; p = Apply[Plus, d]; t = Apply[Times, d]; m = Mod[p + t, n]; If[m == 0, l = Append[l, n]], {n, 2, 10^6}]; l

CROSSREFS

Sequence in context: A322507 A242511 A323268 * A047125 A189238 A226497

Adjacent sequences:  A089745 A089746 A089747 * A089749 A089750 A089751

KEYWORD

nonn

AUTHOR

Joseph L. Pe, Jan 08 2004

STATUS

approved

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Last modified June 17 16:56 EDT 2019. Contains 324196 sequences. (Running on oeis4.)