OFFSET
1,2
COMMENTS
Conjecture: a(n) = a(n+1) for infinitely many positive integers. Largest found is n=4462, i.e. pnd(sd(4462^4462)) = pnd(sd(4463^4463)) = 126.
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..1000
MATHEMATICA
Array[Times@@Select[IntegerDigits[Total[IntegerDigits[#^#]]], #>0&]&, 80] (* Harvey P. Dale, Sep 30 2012 *)
CROSSREFS
KEYWORD
base,easy,nonn
AUTHOR
Jason Earls, Jun 25 2004
STATUS
approved