A135236 Numbers n such that n=s^phi(phi(s)) where s is sum of its digits.

1, 2, 3, 4, 6, 81, 234256, 614656, 1679616, 24794911296, 2518170116818978404827136, 4301431178848799040411011070519998467949638490834092425216

Offset

1,2

Comments

Next term has 96 digits. In fact the sequence has only 14 terms, a(13)=250^40 and a(14)=370^48.

Links

Table of n, a(n) for n=1..12.

Example

24794911296=(2+4+7+9+4+9+1+1+2+9+6)^phi(phi(2+4+7+9+4+9+1+1+2+9+6)) so 24794911296 is in the sequence.

Crossrefs

Cf. A135234, A135235, A135237.

Sequence in context: A067244 A084811 A051856 * A029962 A259388 A049010

Adjacent sequences: A135233 A135234 A135235 * A135237 A135238 A135239

Keyword

base,fini,nonn

Author

Farideh Firoozbakht, Nov 24 2007

Status

approved