A015873 Numbers k such that phi(k + 8) | sigma(k) + 8.

7, 27, 56, 91, 112, 156, 355, 988, 8925, 28518, 36655, 76999, 132943, 360432, 683575, 1412464, 3430111, 11097188, 83623927, 404412907, 288039497527

Offset

1,1

Comments

a(22) > 10^12. - Donovan Johnson, Feb 28 2012

Links

Table of n, a(n) for n=1..21.

Mathematica

Cases[Range[10000],
x_ /; Divisible[DivisorSigma[1, x] + 8, EulerPhi[x + 8]] == True] (* David Nacin, Feb 28 2012 *)

Crossrefs

Sequence in context: A205861 A215446 A098948 * A344721 A309335 A175367

Adjacent sequences: A015870 A015871 A015872 * A015874 A015875 A015876

Keyword

nonn

Author

Robert G. Wilson v

Extensions

Offset corrected and a(10)-a(21) from Donovan Johnson, Feb 28 2012

Status

approved