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A062652
Numbers k such that 86^k - 85^k is prime.
1
5, 11, 103, 227, 1637, 9677, 41597
OFFSET
1,1
COMMENTS
Terms greater than 1000 are often only strong pseudoprimes.
All terms are prime. - Robert Price, Apr 14 2014
a(8) > 10^5. - Robert Price, Apr 14 2015
MATHEMATICA
Select[Range[0, 300], If[PrimeQ[#], PrimeQ[86^# - 85^#]] &] (* Robert Price, Apr 14 2015 *)
PROG
(PARI) is(n)=ispseudoprime(86^n-85^n) \\ Charles R Greathouse IV, Jun 12 2017
CROSSREFS
Cf. A000043, A057468, A059801, A059802, A062572-A062666, A215536 (primes 87^n - 86^n).
Sequence in context: A201074 A056111 A090160 * A075706 A338083 A236509
KEYWORD
nonn,hard
AUTHOR
Mike Oakes, May 18 2001, May 19 2001
EXTENSIONS
a(7) from Robert Price (computer run by Adam Marciniec), Apr 14 2015
STATUS
approved