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A161614 Primes p such that 2*p+100280245065 is also a prime number. 1
41, 43, 89, 127, 137, 157, 193, 211, 233, 241, 251, 271, 283, 317, 331, 353, 389, 401, 419, 461, 487, 503, 521, 547, 557, 613, 619, 751, 787, 827, 857, 919, 929, 937, 941, 953, 1009, 1013, 1021, 1033, 1069, 1097, 1103, 1163, 1171, 1193, 1229, 1361, 1367 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The large constant is constructed from 3*5*7*11*13*17*19*23*29*31 = 100280245065.

LINKS

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

EXAMPLE

The prime 41 is in the sequence because 2*41+100280245065 = 100280245147 is also prime.

MATHEMATICA

a=3*5*7*11*13*17*19*23*29*31; 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, 11]]}, Select[Prime[Range[250]], PrimeQ[ 2#+c]&]] (* Harvey P. Dale, Nov 01 2011 *)

Select[Prime[Range[300]], PrimeQ[2 # + 100280245065]&] (* Vincenzo Librandi, Apr 15 2013 *)

PROG

(MAGMA) [p: p in PrimesUpTo(1400) | IsPrime(2*p + 100280245065)]; // Vincenzo Librandi, Apr 15 2013

CROSSREFS

Sequence in context: A186401 A180548 A157194 * A106098 A155500 A185657

Adjacent sequences:  A161611 A161612 A161613 * A161615 A161616 A161617

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 December 7 05:14 EST 2019. Contains 329839 sequences. (Running on oeis4.)