A066291 Numbers m such that DivisorSigma(8*k-4, m) mod m = 0 holds presumably for all k; that is, (8*k-4)-power-sums of divisors of m are divisible by m for all k.

1, 34, 492, 5617, 11234, 22468, 67404, 190978, 709937, 763912, 1419874, 2839748, 5073996, 5446841, 7914353, 8519244, 10893682, 11548552, 15828706, 17126233, 21787364, 31657412, 34252466, 43574728, 57928121, 63314824, 65362092, 68504932, 73084632, 94972236

Offset

1,2

Links

Table of n, a(n) for n=1..30.

Formula

DivisorSigma(8*k-4, m)/m is an integer for k = 1, 2, 3, ..., 200, ...

Example

Tested for each m with k < 200.
Tested for each m with k < 500. - Sean A. Irvine, Oct 07 2023

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: A241633 A302383 A303104 * A228682 A020929 A160279

Adjacent sequences: A066288 A066289 A066290 * A066292 A066293 A066294

Keyword

nonn

Author

Labos Elemer, Dec 12 2001

Extensions

More terms from Sean A. Irvine, Oct 07 2023

Status

approved