

A103046


Numbers n such that 6*10^n + 8*R_n  1 is prime, where R_n = 11...1 is the repunit (A002275) of length n.


1



0, 1, 33, 72, 177, 192, 325, 417, 732, 1362, 13947, 14887, 32706, 63954, 64783, 82377
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OFFSET

1,3


COMMENTS

Also numbers n such that (62*10^n17)/9 is prime.
a(17) > 10^5.  Robert Price, Sep 15 2015


LINKS

Table of n, a(n) for n=1..16.
Makoto Kamada, Prime numbers of the form 688...887.
Index entries for primes involving repunits.


FORMULA

a(n) = A101539(n1) + 1 for n>1.


MATHEMATICA

Do[ If[ PrimeQ[(62*10^n  17)/9], Print[n]], {n, 0, 10000}]


CROSSREFS

Cf. A002275, A101539.
Sequence in context: A044135 A044516 A015722 * A063868 A184417 A240884
Adjacent sequences: A103043 A103044 A103045 * A103047 A103048 A103049


KEYWORD

more,nonn


AUTHOR

Robert G. Wilson v, Jan 18 2005


EXTENSIONS

a(11)a(12) from Kamada data by Robert Price, Dec 14 2010
a(13) from Erik Branger May 01 2013 by Ray Chandler, Aug 16 2013
Inserted a(1)=0 by Robert Price, Sep 15 2015
a(14)a(16) from Robert Price, Sep 15 2015


STATUS

approved



