login
This site is supported by donations to The OEIS Foundation.
Logo

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A128460 Numbers n such that 19^n - 2 is a prime. 12
1, 2, 3, 13, 14, 19, 20, 23, 38, 1124, 7592, 11755, 12155, 12915, 14172, 15500, 20255, 28388 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

No more terms through 50000. [From Ryan Propper (rpropper(AT)cs.stanford.edu), Dec 04 2008]

MATHEMATICA

Do[ f = 19^n - 2; If[ PrimeQ[ f ], Print[ {n, f} ] ], {n, 1, 1000} ]

CROSSREFS

Cf. A084714 = smallest prime of the form (2n-1)^k - 2, or 0 if no such number exists. Cf. A128472 = smallest prime of the form (2n-1)^k - 2 for k>(2n-1), or 0 if no such number exists. Cf. A014224, A109080, A090669, A128455, A128457, A128458, A128459, A128461.

Sequence in context: A056445 A171483 A100385 * A101541 A059670 A038975

Adjacent sequences:  A128457 A128458 A128459 * A128461 A128462 A128463

KEYWORD

hard,more,nonn

AUTHOR

Alexander Adamchuk (alex(AT)kolmogorov.com), Mar 14 2007

EXTENSIONS

1124 from Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), May 05 2007

7592 from Ryan Propper (rpropper(AT)cs.stanford.edu), Dec 31 2007

Additional terms. Ryan Propper (rpropper(AT)cs.stanford.edu), Dec 04 2008

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified February 15 18:18 EST 2012. Contains 205835 sequences.