

A102944


Numbers n such that 10^n + 8*R_n  5 is prime, where R_n = 11...1 is the repunit (A002275) of length n.


1



1, 16, 22, 28, 34, 90, 2068, 2374, 2854, 3720, 4242, 22666, 29292, 29508
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OFFSET

1,2


COMMENTS

Also numbers n such that (17*10^n53)/9 is prime.
a(15) > 10^5.  Robert Price, Feb 11 2015


LINKS

Table of n, a(n) for n=1..14.
Makoto Kamada, Prime numbers of the form 188...883.
Index entries for primes involving repunits.


FORMULA

a(n) = A102030(n) + 1.


MATHEMATICA

Do[ If[ PrimeQ[(17*10^n  53)/9], Print[n]], {n, 0, 10000}]


CROSSREFS

Cf. A002275, A102030.
Sequence in context: A091118 A294125 A064804 * A058901 A059756 A242214
Adjacent sequences: A102941 A102942 A102943 * A102945 A102946 A102947


KEYWORD

more,nonn


AUTHOR

Robert G. Wilson v, Dec 16 2004


EXTENSIONS

Addition of a(12)a(14) from Kamada data by Robert Price, Dec 12 2010


STATUS

approved



