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A236478 Primes p such that p^3 - p + 1 is prime. 2
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Primes in the sequence A236477.

LINKS

Table of n, a(n) for n=1..51.

EXAMPLE

419 is prime and 419^3 - 419 + 1 = 73559641 is prime. So 419 is a member of this sequence.

PROG

(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

CROSSREFS

Cf. A236477.

Sequence in context: A178899 A023393 A084619 * A106906 A106905 A097159

Adjacent sequences:  A236475 A236476 A236477 * A236479 A236480 A236481

KEYWORD

nonn

AUTHOR

Derek Orr, Jan 26 2014

EXTENSIONS

More terms from Colin Barker, Jan 27 2014

STATUS

approved

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Last modified October 17 14:39 EDT 2019. Contains 328114 sequences. (Running on oeis4.)