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A174179
Numbers n such that 10^n-2^n-1 is prime.
1
1, 3, 9, 15, 180, 747, 1065
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OFFSET
1,2
COMMENTS
a(8) > 50000. -
Jens Kruse Andersen
, Aug 10 2014
LINKS
Table of n, a(n) for n=1..7.
PROG
(Magma) [n: n in [1..700] | IsPrime(10^n-2^n-1) ]
(PARI) is(n)=ispseudoprime(10^n-2^n-1) \\
Charles R Greathouse IV
, Jun 13 2017
CROSSREFS
Cf.
A173852
.
Sequence in context:
A015664
A272621
A134137
*
A076362
A336970
A366051
Adjacent sequences:
A174176
A174177
A174178
*
A174180
A174181
A174182
KEYWORD
nonn
,
hard
,
more
AUTHOR
Vincenzo Librandi
, Mar 11 2010
EXTENSIONS
a(6)-a(7) from
Jens Kruse Andersen
, Aug 10 2014
STATUS
approved
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Last modified April 19 21:09 EDT 2024. Contains 371798 sequences. (Running on oeis4.)