A015823 Numbers k such that phi(k + 7) | sigma(k).

3, 6, 11, 14, 23, 24, 30, 33, 35, 54, 59, 66, 71, 77, 99, 102, 105, 107, 110, 119, 131, 140, 158, 161, 167, 168, 174, 179, 186, 203, 222, 231, 239, 251, 253, 280, 287, 290, 304, 311, 312, 329, 347, 348, 357, 359, 366, 371, 378, 383, 402, 413, 419, 426, 430

Offset

1,1

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..3000

Mathematica

Select[Range[1000], Divisible[DivisorSigma[1, #], EulerPhi[7 + #]] &] (* David Nacin, Mar 01 2012 *)

Prog

(PARI) is(n)=sigma(n)%(eulerphi(n)+7)==0 \\ Charles R Greathouse IV, Sep 25 2012

Crossrefs

Sequence in context: A282277 A122599 A342954 * A049620 A350438 A329741

Adjacent sequences: A015820 A015821 A015822 * A015824 A015825 A015826

Keyword

nonn

Author

Robert G. Wilson v

Status

approved