

A177866


Numbers n such that 10^n  69 is prime.


1



2, 4, 6, 7, 8, 14, 20, 110, 138, 140, 145, 300, 390, 1484, 3194, 3300, 3950, 4986, 5574, 5630, 5874, 8866, 11390, 45130, 86110
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OFFSET

1,1


COMMENTS

The next term, if it exists, is > 100000.
See Kamada link  primecount.txt for terms, primesize.txt for discovery details including probable or proved primes  search on "99931".


LINKS

Table of n, a(n) for n = 1..25
Makoto Kamada, List of nearrepdigitrelated prime numbers.
Index entries for primes involving repunits.


EXAMPLE

10^6  69 = 999931 which is a prime number.


MATHEMATICA

m=1000; For[n=1, n<m, If[PrimeQ[10^n69], Print[n]]; n++ ]


PROG

(PARI) is(n)=ispseudoprime(10^n69) \\ Charles R Greathouse IV, Jun 13 2017


CROSSREFS

Cf. A108330, A108328.
Sequence in context: A015924 A096750 A088458 * A065853 A048284 A026516
Adjacent sequences: A177863 A177864 A177865 * A177867 A177868 A177869


KEYWORD

more,nonn


AUTHOR

Robert Price, Dec 28 2010


EXTENSIONS

a(2425)=45130,86110 from Robert Price, May 29 2011


STATUS

approved



