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A062598
Numbers k such that 32^k - 31^k is prime.
0
5, 1427, 2357, 24499
OFFSET
1,1
COMMENTS
Terms > 1000 often correspond only to strong pseudoprimes.
a(5) > 10^5. - Robert Price, Oct 03 2012
PROG
(PARI) is(n)=ispseudoprime(32^n-31^n) \\ Charles R Greathouse IV, Jun 13 2017
KEYWORD
nonn,hard
AUTHOR
Mike Oakes, May 18 2001, May 19 2001
EXTENSIONS
a(4) from Robert Price, Oct 03 2012
STATUS
approved