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A157978
Primes p such that 4*p - 3 is also a prime.
4
2, 5, 11, 19, 23, 29, 59, 61, 71, 79, 89, 101, 103, 109, 113, 131, 149, 151, 191, 193, 233, 239, 263, 283, 313, 331, 353, 359, 373, 389, 401, 431, 439, 479, 499, 521, 523, 541, 569, 571, 599, 619, 631, 653, 659, 673, 683, 701, 709, 739, 743, 751, 761, 773, 829
OFFSET
1,1
LINKS
MATHEMATICA
q=3; lst={}; Do[p=Prime[n]; If[PrimeQ[(q+1)*p-q], AppendTo[lst, p]], {n, 6!}]; lst
Select[Prime[Range[1000]], PrimeQ[4 # - 3]&] (* Vincenzo Librandi, Feb 03 2014 *)
PROG
(Magma) [n: n in [0..2000] | IsPrime(n) and IsPrime(4*n - 3)]; // Vincenzo Librandi, Feb 03 2014
KEYWORD
nonn,easy
AUTHOR
STATUS
approved