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A062636
Numbers k such that 70^k - 69^k is prime.
0
2, 11, 1301, 78989, 83117
OFFSET
1,1
COMMENTS
Terms greater than 1000 are often only strong pseudoprimes.
a(6) > 10^5. - Robert Price Jan 15 2014
PROG
(PARI) is(n)=ispseudoprime(70^n-69^n) \\ Charles R Greathouse IV, Jun 13 2017
KEYWORD
nonn,hard,bref
AUTHOR
Mike Oakes, May 18 2001, May 19 2001
EXTENSIONS
a(4)-a(5) from Robert Price, Jan 15 2014 (Computer run by Adam Marciniec)
STATUS
approved