login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A155771 Numbers n such that 2*n^2+2*n-41 is a prime. 4
5, 6, 7, 8, 9, 10, 11, 12, 14, 15, 16, 17, 18, 19, 21, 22, 23, 25, 27, 28, 29, 33, 34, 39, 42, 44, 45, 46, 48, 50, 52, 53, 56, 57, 58, 59, 61, 65, 66, 68, 69, 74, 77, 80, 83, 86, 87, 90, 91, 93, 95, 96, 99, 101, 103, 104, 106, 107, 110, 116, 121, 126, 128, 130, 131, 133, 136 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
EXAMPLE
For n=14, a(14)=379; n=140, a(140)=39439.
MATHEMATICA
Select[Range[4, 200], PrimeQ[2#^2+2#-41]&] (* Vincenzo Librandi, Sep 24 2012 *)
PROG
(Magma) [n: n in [4..150] | IsPrime(2*n^2+2*n-41)]; // Vincenzo Librandi, Sep 24 2012
CROSSREFS
Sequence in context: A101107 A296603 A268541 * A138167 A161839 A285619
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Jan 27 2009
STATUS
approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 3 11:29 EST 2024. Contains 370511 sequences. (Running on oeis4.)