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A215536
Numbers n such that 87^n - 86^n is prime.
2
2, 3, 47, 44563
OFFSET
1,1
COMMENTS
a(5) > 10^5. - Robert Price, May 11 2015
MATHEMATICA
Select[Prime[Range[PrimePi[1000]]], PrimeQ[87^# - 86^#] &] (* T. D. Noe, Aug 15 2012 *)
PROG
(PARI) is(n)=ispseudoprime(87^n-86^n) \\ Charles R Greathouse IV, Jun 06 2017
CROSSREFS
Sequence in context: A266512 A041501 A163488 * A173355 A118222 A191594
KEYWORD
nonn,hard
AUTHOR
Jean-Louis Charton, Aug 15 2012
EXTENSIONS
a(4) from Robert Price (computer run by Adam Marciniec), May 11 2015
STATUS
approved