

A110980


Integers n such that 10^n+99 is prime.


4



1, 2, 4, 6, 13, 14, 16, 17, 19, 30, 31, 60, 68, 73, 113, 144, 276, 288, 364, 449, 473, 739, 833, 1171, 1732, 2292, 3912, 7673, 9458, 16982, 19751, 21479, 23837, 77726
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OFFSET

1,2


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 "10w99".


LINKS

Table of n, a(n) for n=1..34.
Makoto Kamada, List of nearrepdigitrelated prime numbers.
Index entries for primes involving repunits.


EXAMPLE

If n=6, we have 10^6+99 = 1000000+99 = 1000099, which is prime.


MATHEMATICA

Select[Range[78000], PrimeQ[10^#+99]&] (* Harvey P. Dale, Aug 23 2013 *)


PROG

(MAGMA) [n: n in [1..400] IsPrime(10^n+99)]; // Vincenzo Librandi, Nov 02 2014


CROSSREFS

Cf. A049054, A088274, A088275, A095688, A107083, A108049, A108050, A108052, A108054.
Sequence in context: A196444 A307617 A325278 * A058598 A332241 A319110
Adjacent sequences: A110977 A110978 A110979 * A110981 A110982 A110983


KEYWORD

more,nonn


AUTHOR

Julien Peter Benney (jpbenney(AT)ftml.net), Sep 30 2005


EXTENSIONS

a(1)=1 added by Vladimir Joseph Stephan Orlovsky, May 02 2008
a(29)a(33) from Robert Price, Mar 22 2010
a(34)=77726 from Robert Price, Mar 03 2011


STATUS

approved



