OFFSET
1,1
COMMENTS
Terms > 1000 are often only strong pseudoprimes.
a(4) > 10^5. - Robert Price, Sep 01 2014
PROG
(PARI) is(n)=ispseudoprime(77^n-76^n) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
KEYWORD
nonn,hard,bref
AUTHOR
Mike Oakes, May 18 2001, May 19 2001
STATUS
approved