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A178438 Numbers n such that 10^n - 83 is prime. 0
2, 6, 16, 42, 47, 62, 109, 191, 221, 509, 3671, 4229, 4886, 6967, 12086 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The next term, if one exists, is > 100000. - Robert Price, Apr 25 2011

See Kamada link - primecount.txt for terms, primesize.txt for discovery details including probable or proved primes - search on "99917".

LINKS

Table of n, a(n) for n=1..15.

Makoto Kamada, List of near-repdigit-related prime numbers

Index entries for primes involving repunits

EXAMPLE

10^6 - 83 = 999917 which is a prime number.

MATHEMATICA

nMax=1000; Do[If[PrimeQ[10^n-83], Print[n]], {n, nMax}]

PROG

(PARI) is(n)=ispseudoprime(10^n-83) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Cf. A108330, A108328.

Sequence in context: A276359 A158920 A263592 * A143123 A102699 A266124

Adjacent sequences:  A178435 A178436 A178437 * A178439 A178440 A178441

KEYWORD

more,nonn

AUTHOR

Robert Price, Dec 21 2010

EXTENSIONS

Example corrected by Patrick De Geest, Nov 28 2014

STATUS

approved

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Last modified September 26 05:09 EDT 2017. Contains 292502 sequences.