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A178434
Numbers n such that 10^n - 71 is prime.
0
2, 3, 4, 5, 7, 9, 10, 14, 22, 98, 127, 151, 158, 274, 377, 1015, 2146, 8499, 13885, 13991, 17834, 18211, 36271, 52317, 53804, 104212, 117059, 178695
OFFSET
1,1
COMMENTS
a(29) > 2.5*10^5. - Robert Price, Apr 12 2015
EXAMPLE
10^4 - 71 = 9929 which is a prime number.
MATHEMATICA
nMax=1000; Do[If[PrimeQ[10^n-71], Print[n]], {n, nMax}]
PROG
(PARI) is(n)=ispseudoprime(10^n-71) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
Sequence in context: A274583 A055600 A139528 * A267439 A262691 A117290
KEYWORD
more,nonn
AUTHOR
Robert Price, Dec 21 2010
EXTENSIONS
a(24:25)=52317,53804 from Robert Price, Apr 25 2011
a(26)-a(28) from Kamada data by Robert Price, Apr 12 2015
STATUS
approved