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A161615 Primes p such that 2*p+3234846615 is also a prime number. 1
31, 43, 71, 73, 89, 107, 139, 179, 211, 223, 241, 269, 271, 281, 293, 311, 317, 337, 379, 383, 389, 419, 443, 449, 467, 503, 563, 569, 587, 607, 647, 653, 727, 739, 743, 757, 761, 811, 839, 857, 863, 881, 941, 967, 977, 991, 1019, 1021, 1049, 1061, 1069, 1087 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The large constant is constructed as 3*5*7*11*13*17*19*23*29 = 3234846615.

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

EXAMPLE

The prime 31 is in the sequence because 2*31 + 3234846615 = 3234846677 is also prime.

MATHEMATICA

a=3*5*7*11*13*17*19*23*29; c=0; lst={}; Do[p=Prime[n]; If[PrimeQ[2*p+a], AppendTo[lst, p], c++ ], {n, 6!}]; lst

With[{c=Times@@Prime[Range[2, 10]]}, Select[Prime[Range[200]], PrimeQ[ 2#+c]&]] (* Harvey P. Dale, Dec 30 2012 *)

Select[Prime[Range[300]], PrimeQ[2 # + 3234846615]&] (* Vincenzo Librandi, Apr 15 2013 *)

PROG

(MAGMA) [p: p in PrimesUpTo(1100) | IsPrime(2*p+3234846615)]; // Vincenzo Librandi, Apr 15 2013

CROSSREFS

Sequence in context: A060844 A112789 A266989 * A307950 A059898 A016108

Adjacent sequences:  A161612 A161613 A161614 * A161616 A161617 A161618

KEYWORD

nonn,less

AUTHOR

Vladimir Joseph Stephan Orlovsky, Jun 14 2009

EXTENSIONS

Definition reworded by R. J. Mathar, Oct 02 2009

STATUS

approved

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Last modified July 12 17:40 EDT 2020. Contains 335665 sequences. (Running on oeis4.)