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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
OFFSET
1,1
LINKS
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
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Apr 12 2016
STATUS
approved