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A108506 Integers n such that 10^n-59 is prime. 4
2, 3, 4, 8, 20, 38, 95, 248, 263, 303, 304, 410, 438, 548, 688, 1074, 1575, 8364, 9910, 15910, 37344 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Certified primality of numbers corresponding to terms 410, 438, 548, 688, 1074 and 1575 with Primo. - Ryan Propper, Jul 08 2005

No other terms <40000.

See Kamada link - primecount.txt for terms, primesize.txt for discovery details including probable or proved primes - search on "99941".

LINKS

Table of n, a(n) for n=1..21.

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

Index entries for primes involving repunits.

EXAMPLE

8 is a member because: n = 8 gives 10^8-59 = 100000000-59 = 99999941, which is prime.

CROSSREFS

Cf. A089675, A095714, A092767, A108327, A108328, A108329, A108330, A108331, A108332, A177418.

Sequence in context: A276673 A282815 A105055 * A129284 A214700 A100997

Adjacent sequences:  A108503 A108504 A108505 * A108507 A108508 A108509

KEYWORD

more,nonn

AUTHOR

Julien Peter Benney (jpbenney(AT)ftml.net), Jul 06 2005

EXTENSIONS

a(18)-a(20) from Kamada data by Robert Price, Dec 10 2010

a(21) by Robert Price, Dec 16 2010

Edited by Ray Chandler, Dec 23 2010

STATUS

approved

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