

A096594


Numbers n such that 100^n + 10^n  1 is prime.


5



1, 2, 3, 5, 6, 7, 9, 13, 26, 42, 153, 188, 204, 282, 699, 2886, 11597
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OFFSET

1,2


COMMENTS

a(1) through a(17) have been proved to be prime with WinPFGW or pfgw.
a(18) > 20000.  Giovanni Resta, Feb 19 2013
a(18) > 100000.  James G. Merickel Jun 02 2014


LINKS

Table of n, a(n) for n=1..17.


EXAMPLE

a(3) = 3 because 100^3 + 10^3  1 = 1000999, a prime.


MATHEMATICA

Select[Range[700], PrimeQ[100^# + 10^#  1] & ] (* Giovanni Resta, Feb 19 2013 *)


PROG

(PARI) is(n)=ispseudoprime(100^n+10^n1) \\ Charles R Greathouse IV, Feb 20 2017


CROSSREFS

Sequence in context: A292938 A056900 A226808 * A100693 A030159 A030161
Adjacent sequences: A096591 A096592 A096593 * A096595 A096596 A096597


KEYWORD

more,nonn


AUTHOR

Jason Earls, Aug 13 2004


EXTENSIONS

a(17) from Giovanni Resta, Feb 19 2013


STATUS

approved



