OFFSET
1,1
COMMENTS
All k<10^10 have been checked. Note that this sequence appears to contain all powers of 3. It also contains 256 and 512, which are the only even numbers listed here.
All k<10^11 have been checked. 65 n values remain < 1000. - Donovan Johnson, Aug 29 2012
REFERENCES
R. K. Guy, Unsolved Problems in Number Theory, 3rd Ed., New York, Springer-Verlag, 2004, Section B15.
CROSSREFS
KEYWORD
nonn
AUTHOR
T. D. Noe, Jul 12 2005
EXTENSIONS
Two terms removed (465 and 711) by Donovan Johnson, Aug 29 2012
STATUS
approved