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A108049

Integers k such that 10^k + 43 is a prime number.

1, 5, 37, 253, 1129, 1441, 35393

OFFSET

1,2

COMMENTS

a(8) > 10^5. - Robert Price, Nov 01 2013

See Kamada link - primecount.txt for terms, primesize.txt for discovery details including probable or proved primes - search on "10043".

LINKS

EXAMPLE

k=5 is a term because 10^5 + 43 = 100043, which is prime.

MATHEMATICA

Select[Range[2*10^3], PrimeQ[10^#+43]&] (* Vladimir Joseph Stephan Orlovsky, Apr 29 2008 *)

PROG

(PARI) is(n)=ispseudoprime(10^n+43) \\ Charles R Greathouse IV, Apr 28 2015

CROSSREFS

KEYWORD

nonn,more,hard

AUTHOR

Julien Peter Benney (jpbenney(AT)ftml.net), Jun 01 2005

EXTENSIONS

a(7)=35393 from Robert Price, Mar 16 2010

Edited by Ray Chandler, Dec 23 2010

STATUS

approved

URL: https://oeis.org/A108049