OFFSET
1,2
COMMENTS
Conjecture: a(n) = a(n+1) for infinitely many positive integers. Largest found is n=2577, i.e. sd(pnd(2577^2577)) = sd(pnd(2578^2578)) = 18315.
CROSSREFS
KEYWORD
base,easy,nonn
AUTHOR
Jason Earls, Jun 24 2004
STATUS
approved