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 A271666 Primes p such that 4*p^2+4*p-1 is prime. 2
 2, 3, 7, 13, 17, 23, 31, 37, 53, 59, 67, 139, 149, 151, 157, 167, 179, 193, 199, 223, 233, 293, 307, 331, 359, 373, 389, 431, 479, 571, 587, 619, 643, 653, 683, 809, 839, 857, 863, 919, 937, 947, 1021, 1091, 1123, 1151, 1187, 1277, 1301, 1367, 1427, 1511 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Vincenzo Librandi, Table of n, a(n) for n = 1..1000 MATHEMATICA Select[Prime[Range[300]], PrimeQ[4 #^2 + 4 # - 1] &] PROG (MAGMA) [p: p in PrimesUpTo(2000) | IsPrime(4*p^2+4*p-1)]; (PARI) lista(nn) = forprime(p=2, nn, if(isprime(4*p^2+4*p-1), print1(p, ", "))); \\ Altug Alkan, Apr 12 2016 (Python) from gmpy2 import is_prime for p in range(3, 10**5, 2):     if(not is_prime(p)):continue     elif(is_prime(6*p**2+6*p-1)):print(p) # Soumil Mandal, Apr 14 2016 CROSSREFS Cf. A171139, A171831, A171832, A261810. Sequence in context: A220814 A045328 A045329 * A106306 A069104 A003631 Adjacent sequences:  A271663 A271664 A271665 * A271667 A271668 A271669 KEYWORD nonn,easy AUTHOR Vincenzo Librandi, Apr 12 2016 STATUS approved

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Last modified January 28 06:29 EST 2020. Contains 331317 sequences. (Running on oeis4.)