A067877 Numbers n such that sigma(n)=phi(n*bigomega(n)-1).

1, 10, 33, 46, 65, 77, 123, 221, 371, 385, 545, 753, 1643, 2033, 2635, 3243, 4311, 4533, 4798, 5177, 5495, 5605, 7463, 7565, 7683, 7739, 8201, 9741, 11679, 13039, 13623, 17147, 17663, 18067, 18695, 23038, 23335, 24215, 27231, 28495, 31403

Offset

1,2

Links

Table of n, a(n) for n=1..41.

Mathematica

Select[Range[32000], DivisorSigma[1, #]==EulerPhi[# PrimeOmega[#]-1]&] (* Harvey P. Dale, Jan 16 2023 *)

Crossrefs

Sequence in context: A256352 A255533 A067878 * A367031 A348427 A063160

Adjacent sequences: A067874 A067875 A067876 * A067878 A067879 A067880

Keyword

easy,nonn

Author

Benoit Cloitre, Mar 02 2002

Status

approved