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A178437
Numbers n such that 10^n - 81 is prime.
0
2, 3, 17, 19, 31, 37, 43, 91, 339, 367, 407, 1135, 1175, 8653, 11987, 15793
OFFSET
1,1
COMMENTS
The next term, if one exists, is >100000. - Robert Price, Apr 25 2011
EXAMPLE
10^3 - 81 = 919 which is a prime number.
MATHEMATICA
nMax=1000; Do[If[PrimeQ[10^n-81], Print[n]], {n, nMax}]
PROG
(PARI) is(n)=ispseudoprime(10^n-81) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
Sequence in context: A135931 A215323 A215351 * A215360 A215380 A215376
KEYWORD
more,nonn
AUTHOR
Robert Price, Dec 21 2010
STATUS
approved