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A066291 Numbers n such that Mod[DivisorSigma[8k-4,n],n]=0 holds presumably for all k; that is (8k-4)-power-sums of divisors of n are divisible by n for all k. 0
1, 34, 492, 5617, 11234, 22468, 67404, 190978 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

FORMULA

DivisorSigma[8k-4, n]/n] is integer for all k=1, 2, 3, .., 200, ...

EXAMPLE

Tested for each n with k<200.

MATHEMATICA

Table[Union[Table[ IntegerQ[DivisorSigma[8*k-4, Part[t, m]]/Part[t, m]], {k, 1, 200}]], {m, 1, Length[t]}]; where t denotes the table of sequence.

CROSSREFS

Cf. A066135, A066284, A066289-A066292.

Sequence in context: A189452 A159655 A107917 * A020929 A160279 A133720

Adjacent sequences:  A066288 A066289 A066290 * A066292 A066293 A066294

KEYWORD

nonn

AUTHOR

Labos E. (labos(AT)ana.sote.hu), Dec 12 2001

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Last modified February 16 21:17 EST 2012. Contains 205971 sequences.