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A236478
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Primes p such that p^3 - p + 1 is prime.
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3
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2, 7, 11, 19, 31, 41, 101, 139, 167, 239, 271, 277, 307, 347, 419, 449, 479, 491, 521, 547, 557, 587, 617, 619, 631, 647, 739, 757, 761, 769, 787, 809, 827, 839, 857, 971, 977, 991, 1019, 1069, 1187, 1201, 1217, 1231, 1277, 1487, 1621, 1637, 1709, 1747, 1861
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OFFSET
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1,1
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COMMENTS
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LINKS
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EXAMPLE
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419 is prime and 419^3 - 419 + 1 = 73559641 is prime. So 419 is a member of this sequence.
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MATHEMATICA
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Select[Prime[Range[300]], PrimeQ[#^3-#+1]&] (* Harvey P. Dale, Oct 30 2021 *)
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PROG
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(Python)
import sympy
from sympy import isprime
{print(n) for n in range(10**4) if isprime(n) and isprime(n**3-n+1)}
(PARI)
s=[]; forprime(p=2, 2000, if(isprime(p^3-p+1), s=concat(s, p))); s \\ Colin Barker, Jan 27 2014
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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