OFFSET
1,2
COMMENTS
Conjecture: sequence is finite.
EXAMPLE
11, (13 and 131), (139, 13931), (13913 and 139131931), etc. are all prime.
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Sep 23 2003
EXTENSIONS
More terms from David Wasserman, Jul 15 2005
STATUS
approved