A079541 Numbers n such that phi(n) = d(n).

1, 3, 8, 10, 18, 24, 30

Offset: 1

Author

N. J. A. Sloane, Jan 23 2003

Keywords

• dead

Comments

Duplicate of A020488. - Peter Luschny, Aug 26 2011

References

• D. S. Mitrinovic et al., Handbook of Number Theory, Kluwer, p. 11.

Crossrefs

Cf. A000010, A000005, A063070.

Programs

Mathematica

Select[Range[500],EulerPhi[#]==DivisorSigma[0,#]&] (* Harvey P. Dale, Jun 18 2011 *)

Extensions

Corrected by Harvey P. Dale, Jun 18 2011