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

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A125113 Numbers n such that 2n-1, 4n-1, 8n-1, 16n-1, 32n-1 and 64n-1 are primes. 6
45, 31710, 63570, 202635, 405405, 534600, 561330, 589305, 666945, 799350, 903045, 979125, 1082115, 1122660, 1164735, 1303035, 1424475, 1620645, 1669995, 1892100, 1981020, 2044440, 2164230, 2222415, 2329470, 2332125, 2447445, 2448855 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..28.

MATHEMATICA

Select[15*Range[200000], And @@ PrimeQ /@ ({2, 4, 8, 16, 32, 64}*# - 1) &] (*Chandler*)

CROSSREFS

Cf. A006254, A124485, A124493, A124494, A124017, A124514, A124515, A124516.

Sequence in context: A199521 A007537 A225991 * A003739 A145319 A089626

Adjacent sequences:  A125110 A125111 A125112 * A125114 A125115 A125116

KEYWORD

nonn

AUTHOR

Artur Jasinski, Nov 22 2006

EXTENSIONS

Extended by Ray Chandler, Nov 22 2006

STATUS

approved

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 May 25 01:58 EDT 2013. Contains 225634 sequences.