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!)
A237814 Primes p such that 2*p+1 and 2*p+19 are also prime. 5
2, 5, 11, 41, 89, 131, 191, 251, 419, 431, 641, 809, 1031, 1229, 1409, 1439, 1511, 1559, 1601, 1889, 1901, 1931, 2069, 2351, 2399, 2459, 2699, 2741, 2819, 2939, 3359, 3449, 3491, 3761, 3779, 3911, 4409, 4919, 5081, 5849, 6131, 6449, 6491, 6551, 7079, 7151 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
EXAMPLE
11 is in the sequence because 11, 2*11+1 = 23 and 2*11+19 = 41 are all prime.
MATHEMATICA
Select[Prime[Range[8000]], PrimeQ[2 # + 1] && PrimeQ[2 # + 19] &] (* Vincenzo Librandi, Feb 15 2014 *)
PROG
(PARI) s=[]; forprime(p=2, 10000, if(isprime(2*p+1) && isprime(2*p+19), s=concat(s, p))); s
(Magma) [p: p in PrimesUpTo(8000) | IsPrime(2*p+1) and IsPrime(2*p+19)]; // Vincenzo Librandi, Feb 15 2014
CROSSREFS
Sequence in context: A065850 A191029 A106886 * A007700 A071313 A172297
KEYWORD
nonn
AUTHOR
Colin Barker, Feb 13 2014
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 28 08:22 EDT 2024. Contains 371236 sequences. (Running on oeis4.)