OFFSET
1,1
COMMENTS
Terms greater than 1000 may correspond to (unproven) strong pseudoprimes. [Clarified by M. F. Hasler, Sep 16 2013]
PROG
(PARI) is(n)=ispseudoprime(13^n-12^n) \\ Charles R Greathouse IV, Jun 12 2017
CROSSREFS
KEYWORD
nonn,hard
AUTHOR
Mike Oakes, May 18 2001, May 19 2001
EXTENSIONS
Two more terms 30271 and 87557 (found in 2007 and 2008) from Jean-Louis Charton, Sep 02 2009
STATUS
approved