

A135236


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


3



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



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



KEYWORD

base,fini,nonn


AUTHOR



STATUS

approved



