

A103071


Numbers n such that 8*10^n + R_n + 2 is prime, where R_n = 11...1 is the repunit (A002275) of length n.


1



1, 10, 24, 199, 745, 7753, 17938, 21319, 24948, 26119, 29454, 51889, 62824, 88105
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OFFSET

1,2


COMMENTS

Also numbers n such that (73*10^n+17)/9 is prime.
a(15) > 10^5.  Robert Price, Oct 16 2015


LINKS

Table of n, a(n) for n=1..14.
Makoto Kamada, Prime numbers of the form 811...113.
Index entries for primes involving repunits.


FORMULA

a(n) = A101058(n) + 1.


MATHEMATICA

Do[ If[ PrimeQ[(73*10^n + 17)/9], Print[n]], {n, 0, 10000}]


CROSSREFS

Cf. A002275, A101058.
Sequence in context: A261807 A135285 A235940 * A264296 A265150 A057462
Adjacent sequences: A103068 A103069 A103070 * A103072 A103073 A103074


KEYWORD

more,nonn


AUTHOR

Robert G. Wilson v, Jan 19 2005


EXTENSIONS

a(7)a(11) from Kamada data by Robert Price, Dec 14 2010
a(12)a(14) from Robert Price, Oct 16 2015


STATUS

approved



